Publications by authors named "Jonathan Purnell"

Obesity and type 2 diabetes are prevalent chronic diseases effectively managed by semaglutide. Here we studied the effects of semaglutide on the circulating proteome using baseline and end-of-treatment serum samples from two phase 3 trials in participants with overweight or obesity, with or without diabetes: STEP 1 (n = 1,311) and STEP 2 (n = 645). We identified evidence supporting broad effects of semaglutide, implicating processes related to body weight regulation, glycemic control, lipid metabolism and inflammatory pathways.

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Background: An international panel of obesity medicine experts from multiple professional organizations examined patterns of obesity care and current obesity treatment guidelines to identify areas requiring updating in response to emerging science and clinical evidence.

Aims: The panel focused on multiple medical health and societal issues influencing effective treatment of obesity and identified several unmet needs in the definition, assessment, and care of obesity.

Methods: The panel was held in Leesburg, Virginia in September 2019.

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Background: Hypothalamic centres have been recognized to play a central role in body weight regulation for nearly 70 years.

Aims: In this review, we will explore the current undersanding of the role the hypothalamus plays in controlling food intake behaviours.

Materials And Methods: Review of relevant literature from PubMed searches and review article citations.

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Objective: Given the complex interaction among the circadian system, energy metabolism, and obesity, the authors tested whether having obesity impacts the circadian variation in energy and glucose metabolism in humans.

Methods: Participants with BMI either in the healthy weight or obesity ranges were studied in a 5-day, in-laboratory protocol that equally distributed behaviors (i.e.

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Objective: This observational study investigated metabolomic changes in individuals with type 2 diabetes (T2D) after weight loss. We hypothesized that metabolite changes associated with T2D-relevant phenotypes are signatures of improved health.

Methods: Fasting plasma samples from individuals undergoing bariatric surgery (n = 71 Roux-en-Y gastric bypass [RYGB], n = 22 gastric banding), lifestyle intervention (n = 66), or usual care (n = 14) were profiled for 139 metabolites before and 2 years after weight loss.

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Background: Fatigue can be a disabling multiple sclerosis (MS) symptom with no effective treatment options.

Objective: Determine whether a low-fat diet improves fatigue in people with MS (PwMS).

Methods: We conducted a 16-week randomized controlled trial (RCT) and allocated PwMS to a low-fat diet (active, total daily fat calories not exceeding 20%) or wait-list (control) group.

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Advances in the understanding of weight regulation provide the framework for the recognition of obesity as a chronic disease. Lifestyle approaches are foundational in the prevention of obesity and should be continued while weight management interventions, including antiobesity medications and metabolic-bariatric procedures, are offered to eligible patients. Clinical challenges remain, however, including overcoming obesity stigma and bias within the medical community toward medical and surgical approaches, ensuring insurance coverage for obesity management (including medications and surgery), and promoting policies that reverse the upward worldwide trend in obesity and adiposity complications in populations.

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Article Synopsis
  • Physical frailty significantly impacts health-related quality of life (HRQOL) and clinical outcomes in heart failure (HF), with notable differences between sexes.
  • In a study of 115 adults with HF, frailty was linked to poorer overall HRQOL in women, while it affected physical HRQOL in both men and women.
  • Men showed a higher risk of clinical events (like hospitalization) with increased frailty scores, but this association was not found in women, highlighting the need for further exploration of sex-specific health issues in HF.
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Background: Obesity leads to insulin resistance, altered lipoprotein metabolism, dyslipidemia, and cardiovascular disease. The relationship between long-term intake of n-3 polyunsaturated fatty acids (n-3 PUFAs) and prevention of cardiometabolic disease remains unresolved.

Objectives: The aim of this study was to explore direct and indirect pathways between adiposity and dyslipidemia, and the degree to which n-3 PUFAs moderate adiposity-induced dyslipidemia in a population with highly variable n-3 PUFA intake from marine foods.

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Purpose: To determine the effect of an off-protocol meal during a long-term ad libitum feeding study on changes in total caloric consumption and ratings of hunger and satiety.

Methods: During the ad libitum portion of a 16 weeks research high-protein feeding study, 19 participants were allowed to eat up to one self-selected meal (SSM) a week instead of an intervention diet meal. The SSM was assessed for total caloric and macronutrient composition and compared to the intervention diet for 3 days before and after the SSM day.

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The National Kidney Foundation (NKF) and The Obesity Society (TOS) cosponsored a multispecialty international workshop in April 2021 to advance the understanding and management of obesity in adults with chronic kidney disease (CKD). The underlying rationale for the workshop was the accumulating evidence that obesity is a major contributor to CKD and adverse outcomes in individuals with CKD, and that effective treatment of obesity, including lifestyle intervention, weight loss medications, and metabolic surgery, can have beneficial effects. The attendees included a range of experts in the areas of kidney disease, obesity medicine, endocrinology, diabetes, bariatric/metabolic surgery, endoscopy, transplant surgery, and nutrition, as well as patients with obesity and CKD.

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The National Kidney Foundation (NKF) and The Obesity Society (TOS) cosponsored a multispecialty international workshop in April 2021 to advance the understanding and management of obesity in adults with chronic kidney disease (CKD). The underlying rationale for the workshop was the accumulating evidence that obesity is a major contributor to CKD and adverse outcomes in individuals with CKD, and that effective treatment of obesity, including lifestyle intervention, weight loss medications, and metabolic surgery, can have beneficial effects. The attendees included a range of experts in the areas of kidney disease, obesity medicine, endocrinology, diabetes, bariatric/metabolic surgery, endoscopy, transplant surgery, and nutrition, as well as patients with obesity and CKD.

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Article Synopsis
  • - The study aimed to identify biomarkers linked to physical frailty in heart failure (HF) patients by analyzing various biological markers tied to different bodily processes.
  • - Researchers collected data from 113 HF patients, assessing their frailty using specific criteria and measuring several plasma biomarkers. They found that 42% of participants were physically frail, with links to factors like gender and body composition.
  • - The analysis revealed that lower levels of adiponectin, IGF-1, and myostatin were associated with physical frailty, particularly in men, indicating these biomarkers play a role in the maintenance of muscle and fat tissue in HF patients.
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Aim: Obesity is a significant health issue for participants with type 1 diabetes undergoing intensive diabetes management. The temporal pattern and factors associated with weight gain after treatment initiation remain poorly understood including how weight gain in participants with and without type I diabetes compare. Our aim was to compare weight gain in those receiving intensive (INT) and conventional (CONV) type 1 diabetes treatment to a population without diabetes.

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Background: Excessive gestational weight gain has been associated with increased total body fat (TBF), metabolic syndrome, and abdominal obesity. However, little is known about the relationship of gestational weight gain with changes in metabolically active visceral or ectopic (hepatic and skeletal muscle) lipid stores.

Objectives: In a prospective study of 50 healthy, pregnant women, we assessed whether changes in weight were associated with changes in total, visceral, and ectopic lipid stores.

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Article Synopsis
  • * Women who adopt healthy eating patterns during pregnancy may experience fewer complications and better outcomes for their children, with proper nutrition linked to improved birth weights.
  • * Tools and guidance are needed for women to evaluate their diets, highlighting that both prepregnancy obesity and inadequate weight gain during pregnancy can negatively impact perinatal health.
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Background: Lipid management for prevention and treatment of cardiovascular disease remains insufficient for many with currently available therapies.

Objective: Evaluate real-world use of bempedoic acid.

Methods: Retrospective study of patients in our Center for Preventive Cardiology who were prescribed bempedoic acid between February 2020 and July 2021.

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Background: The relationship between dietary n-3 PUFAs and the prevention of cardiometabolic diseases, including type 2 diabetes, is unresolved. Examination of the association between n-3 PUFAs and chronic low-grade inflammation in a population where many individuals have had an extremely high intake of marine mammals and fish throughout their lifespan may provide important clues regarding the impact of n-3 PUFAs on health.

Objectives: The aim of this study was to explore associations between concentrations of n-3 PUFAs resulting from habitual intake of natural food sources high in fish and marine mammals with immune biomarkers of metabolic inflammation and parameters of glucose regulation.

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During pregnancy, the rodent liver undergoes hepatocyte proliferation and increases in size, followed by weaning-induced involution via hepatocyte cell death and stromal remodeling, creating a prometastatic niche. These data suggest a mechanism for increased liver metastasis in breast cancer patients with recent childbirth. It is unknown whether the human liver changes in size and function during pregnancy and weaning.

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