Leptin is produced not only in the adipose tissue but also in the gastrointestinal tract, particularly in the stomach, where it has been shown to protect the gastric mucosa against various topical irritants and ulcerogens, acting, at least in part, via enhancement of mucosal blood flow due to increased production of nitric oxide (NO) caused by upregulation of NO synthase as well as the activation of brain-gut axis pathways (48, 49)
This coordinated multi-organ response is what allows GLP-1 to orchestrate complex metabolic changes from a single hormonal message
Beyond pancreatic effects, GIP receptor agonism enhances peripheral insulin sensitivity, particularly in adipose tissue, where it promotes healthy white adipose tissue (WAT) expansion, facilitates dietary triglyceride clearance through increased lipoprotein lipase activity and adipose blood flow, and improves lipid buffering capacity [40]
The Lancet , 402 (10402), 613-626
For you as someone considering or using these medications, the practical takeaway is straightforward