Endocrine Abstracts

Background: Rare genetic disorders of obesity result from an impaired central melanocortin pathway, comprised of multiple genes, including POMC, PCSK1, and LEPR. Because of their rarity and the difficulty in identifying individuals with pathogenic mutations in these genes, a complete understanding of these disorders remains unclear. We reviewed previous case reports of individuals with POMC, PCSK1, or LEPR deficiencies to understand their cl...

Background: IRS2-deficient (IRS2-/-) mice are considered a good model to analyze the development of diabetes as some of them present an increase in glycemia comparable to that observed in diabetes onset in humans, whereas a high proportion of these mice do not develop diabetes. Energy homeostasis regulation by the hypothalamus can be disturbed by an inflammatory environment, which predisposes an individual to the onset of diabetes. Saturated fatty acids induce hypot...

Background: Brown adipose tissue (BAT) plays a pivotal role in the regulation of energy homeostasis and thermogenesis. This tissue responds to insulin, favoring the expression of uncoupling protein-1 (UCP-1), that in turn is inhibited by insulin-desensitizing cytokines. Leptin may abolish some of the effects of fasting on these parameters through its cross-talk with insulin-related signaling targets.Objectives: We hypothesized that leptin infusion preven...

Background: Proopiomelanocortin (POMC; including biallelic variants in PCSK1) and leptin receptor (LEPR) deficiency are associated with hyperphagia and early-onset, severe obesity. Treatment with the melanocortin-4 receptor agonist setmelanotide for 1 year results in significant and sustained improvements in weight (POMC, −25.6%; LEPR, −12.5%), hunger, and quality of life. We used the metabolic syndrome Z score based on body mass index (MetS-Z-BMI) to asse...

Background: Rare variants in the melanocortin-4 receptor (MC4R) pathway are associated with early-onset, severe obesity and hyperphagia. Setmelanotide, an MC4R agonist, reduced body mass index (BMI) and decreased hunger in patients with obesity due to biallelic variants in genes encoding proopiomelanocortin (POMC), proprotein convertase subtilisin/kexin type 1 (PCSK1), or leptin receptor (LEPR) in Phase 3 trials. The current analysis assesses the durability of setmelanotide ef...

Objective: Ideally, treatment strategies designed to reduce weight or body mass index in patients with obesity should reduce fat mass while preserving lean mass because reduced lean mass can negatively impact overall health and energy expenditure, thus favoring weight regain. In Phase 3 trials, 1 year of treatment with the melanocortin-4 receptor agonist setmelanotide led to weight reduction in patients with obesity due to biallelic variants in the genes encoding proopiomelano...

Background: Congenital isolated ACTH deficiency (IAD) is a rare condition characterised by low plasma ACTH and serum cortisol with normal production of other pituitary hormones. TBX19 is a T-box pituitary restricted transcription factor important for POMC gene transcription and terminal differentiation of POMC-expressing cells. TBX19 gene mutations have been shown to cause neonatal-onset congenital IAD. To date 25 mutations in TBX19 have been described, five ...

Background: Patients with Bardet-Biedl syndrome (BBS), a rare syndrome associated with obesity and hyperphagia, commonly manifest traits of metabolic syndrome, including abdominal obesity, impaired fasting glucose, low high-density lipoprotein cholesterol, hypertriglyceridemia, and hypertension. Setmelanotide treatment results in significant improvement in weight, hunger, and quality of life in these patients and may improve measures associated with metabolic syndrome developm...

Background: In patients with Bardet-Biedl syndrome (BBS), signaling impairments in the melanocortin-4 receptor (MC4R) pathway lead to hyperphagia and severe obesity, which negatively impact quality of life (QOL). We evaluated the impact of setmelanotide, an MC4R agonist, on age-appropriate weight-related parameters, hunger, and QOL in a Phase 3 trial of patients with BBS to further characterize clinical benefit in this patient population.Methods: Patient...

Background: Patients with proopiomelanocortin (POMC; including variants in POMC or PCSK1) or leptin receptor (LEPR) deficiency due to biallelic gene variants have impaired melanocortin-4 receptor signaling that leads to hyperphagia and early-onset, severe obesity. Setmelanotide treatment in this population improved weight-related measures and hunger severity and was well tolerated. Reported here are long-term extension (LTE) outcomes after 4 years of setmelan...