The motilin receptor agonist erythromycin stimulates hunger and food intake through a cholinergic pathway.
BACKGROUND
Motilin-induced phase III contractions have been identified as a hunger signal. These phase III contractions occur as part of the migrating motor complex (MMC), a contractility pattern of the gastrointestinal tract during fasting. The mechanism involved in this association between subjective hunger feelings and gastrointestinal motility during the MMC is largely unknown, however, as is its ability to stimulate food intake.


OBJECTIVES
We sought to 1) investigate the occurrence of hunger peaks and their relation to phase III contractions, 2) evaluate whether this relation was cholinergically driven, and 3) assess the ability of the motilin receptor agonist erythromycin to induce food intake.


DESIGN
An algorithm was developed to detect hunger peaks. The association with phase III contractions was studied in 14 healthy volunteers [50% men; mean ± SEM age: 25 ± 2 y; mean ± SEM body mass index (BMI; in kg/m(2)): 23 ± 1]. The impact of pharmacologically induced phase III contractions on the occurrence of hunger peaks and the involvement of a cholinergic pathway were assessed in 14 healthy volunteers (43% men; age: 29 ± 3 y; BMI: 23 ± 1). Last, the effect of erythromycin administration on food intake was examined in 15 healthy volunteers (40% men; age: 28 ± 3 y; BMI: 22 ± 1).


RESULTS
The occurrence of hunger peaks and their significant association with phase III contractions was confirmed (P < 0.0001). Pharmacologically induced phase III contractions were also significantly associated with hunger peaks (P < 0.05), and this association involved a cholinergic pathway. Administering erythromycin significantly stimulated food intake compared with placebo (53% ± 13% compared with 10% ± 5%; P < 0.05).


CONCLUSIONS
Motilin-induced phase III contractions induced hunger feelings through a cholinergic pathway. Moreover, erythromycin stimulated food intake, suggesting a physiologic role of motilin as an orexigenic signal from the gastrointestinal tract. This trial was registered at www.clinicaltrials.gov as NCT02633579.
['Deloose|Eveline|E|', 'Vos|Rita|R|', 'Janssen|Pieter|P|', 'Van den Bergh|Omer|O|', 'Van Oudenhove|Lukas|L|', 'Depoortere|Inge|I|', 'Tack|Jan|J|http://orcid.org/0000-0002-3206-6704']
D000328:Adult D018678:Cholinergic Agents D004435:Eating D004917:Erythromycin D005215:Fasting D005260:Female D005765:Gastrointestinal Agents D006801:Humans D006815:Hunger D008297:Male D009037:Motilin D009119:Muscle Contraction D016065:Myoelectric Complex, Migrating D011964:Receptors, Gastrointestinal Hormone D018013:Receptors, Neuropeptide D016037:Single-Blind Method D055815:Young Adult
motilin erythromycin hunger food intake migrating motor complex