Secretin modulates appetite via brown adipose tissue-brain axis

Area of Science:

• Neuroscience
• Metabolism
• Endocrinology

Background:

• Secretin is known to activate brown adipose tissue (BAT) and induce satiety in both mice and humans.
• The precise neural mechanisms governing the secretin-mediated gut-BAT-brain axis for satiety remain largely unexplored.

Purpose of the Study:

• To elucidate the brain mechanisms by which secretin induces satiety.
• To investigate the role of the gut-BAT-brain axis in secretin-mediated appetite regulation.

Main Methods:

• A placebo-controlled, single-blinded neuroimaging study.
• Utilized [18F]-fluorodeoxyglucose (FDG) PET scans to measure brain glucose consumption (n=15).
• Employed functional magnetic resonance imaging (fMRI) to assess brain activity and inhibitory control (n=14).
• Conducted PET-fMRI fusion analysis to correlate metabolic and neural activity (n=10).

Main Results:

• Secretin modulated brain glucose consumption, with significant negative correlation between BAT and caudate glucose uptake during secretin administration (r=-0.54, p=0.037).
• Secretin administration enhanced inhibitory control and reduced brain responses to appetizing food cues.
• PET-fMRI fusion revealed patterned correspondence between caudate glucose uptake and neural activity related to reward and inhibition.

Conclusions:

• Secretin modulates BAT-brain metabolic crosstalk, influencing neurometabolic coupling to induce satiation.
• Findings advance the understanding of secretin signaling in motivated eating behavior.
• Suggests potential therapeutic applications of secretin for eating disorders and obesity.