Effect of Antral Motility on Food Hydrolysis and Gastric Emptying from the Stomach: Insights from Computational Models

Abstract

The peristaltic motion of the stomach walls combines with the secretion of enzymes to initiate the process that breaks down food. Computational modelling of this phenomenon can help reveal the details that would be hard to capture via in-vivo or in-vitro means. In this study, the digestion of a liquid meal containing protein is simulated in a human-stomach model based on imaging data. Pepsin, the gastric enzyme for protein hydrolysis, is secreted from the proximal region of the stomach walls and allowed to react with the contents of the stomach. The jet velocities, the emptying rate, and the extent of hydrolysis are quantified for a control case, and also for three other cases of reduced motility with varying peristaltic amplitudes. The findings quantify the effect of motility on the rate of food breakdown and emptying, and correlate the observations with the mixing in the stomach induced by the antral contraction waves.

Calibration of a physics-based human gastric emptying model

“…Subsequently, Ferrua and Singh et al (2010) developed a 3D model of gastric mixing in a stomach with closed pylorus. In recent years, the Imai (Ebara et al, 2023;Ishida et al, 2019) and Mittal (Kuhar et al, 2022;Seo and Mittal, 2021) groups have separately developed models of gastric fluid dynamics in anatomically realistic 3D stomach geometries, coupled with peristaltic ACWs and periodic pyloric opening. Previously, our group also developed a Smoothed-particle hydrodynamics (SPH) model to investigate emptying of an aqueous digesta (Harrison et al, 2018) through an open pylorus under the effect of peristalsis.…”