Early Effect of Single-dose Sitagliptin Administration on Gastric Emptying: Crossover Study Using the 13C Breath Test

BACKGROUND/AIMS: The gastrointestinal motility effects of endogenous incretin hormones enhanced by dipeptidyl peptidase-IV (DPP-IV) inhibitors have not yet been sufficiently investigated. The aim of this study was to determine whether single pre-prandial sitagliptin, the DPP-IV inhibitor, administration might have an effect on the rate of liquid gastric emptying using the 13C-acetic acid breath test. METHODS: Ten healthy male volunteers participated in this randomized, two-way crossover study. The subjects fasted for overnight and were randomly assigned to receive 50 mg sitagliptin 2 hours before ingestion of the liquid test meal (200 kcal per 200 mL, containing 100 mg 13C-acetate) or the test meal alone. Under both conditions, breath samples were collected for 150 minutes following the meal. Liquid gastric emptying was estimated by the values of the following parameters: the time required for 50% emptying of the labeled meal (T1/2), the analog to the scintigraphy lag time for 10% emptying of the labeled meal (Tlag), the gastric emptying coefficient and the regression-estimated constants (beta and kappa), calculated by using the 13CO2 breath excretion curve using the conventional formulae. The parameters between the 2 test conditions were compared statistically. RESULTS: No significant differences in the calculated parameters, including T1/2, Tlag, gastric emptying coefficient or beta and kappa, were observed between the 2 test conditions. CONCLUSIONS: The present study revealed that single-dose sitagliptin intake had no significant influence on the rate of liquid gastric emptying in asymptomatic volunteers.

Change of Gastric Emptying With Chewing Gum: Evaluation Using a Continuous Real-Time 13C Breath Test (BreathID System)

BACKGROUND/AIMS: There are few reports on the correlation between chewing gum and the gastrointestinal functions. But previous report showed use of chewing gum to be an effective method for controlling gastrointestinal symptoms. The aim of this study was to determine the correlation between chewing gum and gastric emptying using the continuous real time 13C breath test (BreathID system). METHODS: Ten healthy male volunteers participated in this randomized, 2-way crossover study. The subjects fasted overnight and were randomly assigned to chewing gum (Xylish, 2-3/1 tablet) for an hour following intake of a test meal (200 kcal/200 mL) or intake of the test meal alone. Gastric emptying was monitored for 4 hours after administration of the test meal by the 13C-acetic acid breath test performed continually using the BreathID system. RESULTS: No significant differences in the calculated parameters, namely, T1/2 (median, 111.82 vs 109.26 minutes; P = 0.575), Tlag (median, 53.28 vs 56.53 minutes; P = 0.333), gastric emptying coefficient (median, 3.58 vs 3.65; P = 0.285), regression-estimated constant beta (median, 1.85 vs 1.80; P = 0.575) and regression-estimated constant kappa (median, 0.61 vs 0.62; P = 0.959) were observed between the test meal alone group and the test meal and chewing gum group. CONCLUSIONS: This study showed that chewing gum had no effect on the rate of gastric emptying. Therefore, since chewing gum did not enhance the speed of gastric emptying, it may ameliorate gastrointestinal symptoms through other mechanisms, such as saliva and autonomic nervous system.