Which effect is hypothesized to be mediated by GIP receptor activation in obesity therapies?

Which effect is hypothesized to be mediated by GIP receptor activation in obesity therapies?

• A. Increased insulin secretion and delayed gastric emptying
• B. Delayed gastric emptying and suppression of postprandial glucagon
• C. Increased glucagon secretion and modulation of dopaminergic signaling in the limbic system
• D. Increased adipose tissue blood flow and adipocyte metabolism

Answer: (C)

GIP receptor activation in obesity therapies is thought to influence both pancreatic hormone release and brain reward pathways. When GIP binds its receptor on pancreatic cells, it can stimulate glucagon secretion, especially in the context of varying glucose levels. This glucagon-related effect is part of how GIP signaling may help modulate energy balance. At the same time, GIP receptors are present in brain regions of the limbic system that regulate reward and motivation, and activating these receptors can modulate dopaminergic signaling there. The combination of increased glucagon secretion and altered limbic dopamine signaling is the proposed mechanism by which GIP receptor activation could influence weight management. Delayed gastric emptying is primarily a GLP-1–mediated effect, and while adipose tissue actions can occur, the central hypothesized mediator in this context is the joint peripheral glucagon effect and brain reward modulation.

GIP receptor activation in obesity therapies is thought to influence both pancreatic hormone release and brain reward pathways. When GIP binds its receptor on pancreatic cells, it can stimulate glucagon secretion, especially in the context of varying glucose levels. This glucagon-related effect is part of how GIP signaling may help modulate energy balance. At the same time, GIP receptors are present in brain regions of the limbic system that regulate reward and motivation, and activating these receptors can modulate dopaminergic signaling there. The combination of increased glucagon secretion and altered limbic dopamine signaling is the proposed mechanism by which GIP receptor activation could influence weight management. Delayed gastric emptying is primarily a GLP-1–mediated effect, and while adipose tissue actions can occur, the central hypothesized mediator in this context is the joint peripheral glucagon effect and brain reward modulation.