Naringenin stimulates cholecystokinin secretion in STC-1 cells

BACKGROUND/OBJECTIVES Cholecystokinin (CCK), a hormone or neuropeptide, is secreted in response to intraluminal nutrients by enteroendocrine I-cells of the intestine and has important physiological actions related to appetite regulation and satiety. The stimulation on CCK secretion from the intestine is of potential relevance for body weight management. Naringenin (4',5,7-trihydroxyflavanone) and its glycoside naringin (naringenin 7-rhamnoglucoside) have been reported to have many biological functions. In the current study, we investigated the question of whether naringenin and naringin could stimulate CCK secretion and then examined the mechanisms involved in CCK release. MATERIALS/METHODS STC-1 cells were used as a model of enteroendocrine cells. CCK release and changes in intracellular Ca(2+) ([Ca(2+)]i) were measured after incubation of cells with naringenin and naringin for 1 h. RESULTS Naringenin caused significant (P < 0.05) stimulation of CCK secretion, but naringin did not. In addition, regarding the secretory mechanisms, naringenin-induced CCK secretion involved increases in [Ca(2+)]i, influx of extracellular Ca(2+), at least in part, and activation of TRP channels, including TRPA1. CONCLUSION Findings of this study suggest that naringenin could have a role in appetite regulation and satiety.