Gastrointestinal Simulation Model TWIN-SHIME Shows Differences between Human Urolithin-Metabotypes in Gut Microbiota Composition, Pomegranate Polyphenol Metabolism, and Transport along the Intestinal Tract

Abstract

A TWIN-SHIME system was used to compare the metabolism of pomegranate polyphenols by the gut microbiota from two individuals with different urolithin metabotypes. Gut microbiota, ellagitannin metabolism, short-chain fatty acids (SCFA), transport of metabolites, and phase II metabolism using Caco-2 cells were explored. The simulation reproduced the in vivo metabolic profiles for each metabotype. The study shows for the first time that microbial composition, metabolism of ellagitannins, and SCFA differ between metabotypes and along the large intestine. The assay also showed that pomegranate phenolics preserved intestinal cell integrity. Pomegranate polyphenols enhanced urolithin and propionate production, as well as Akkermansia and Gordonibacter prevalence with the highest effect in the descending colon. The system provides an insight into the mechanisms of pomegranate polyphenol gut microbiota metabolism and absorption through intestinal cells. The results obtained by the combined SHIME/Caco-2 cell system are consistent with previous human and animal studies and show that although urolithin metabolites are present along the gastrointestinal tract due to enterohepatic circulation, they are predominantly produced in the distal colon region.

Amoxicillin exposure significantly increases the population and virulence of antibiotic-resistant Klebsiella pathogen in the simulated human intestinal microbiota

“…Meanwhile, the largest increase of predicted human disease-related pathways was also shown in ascending colon after AMX exposure (Fig. 2), which clarified that the primary effect observed at the level of the microbiota could also be identified at the genomic and metabolic level, as reported in other researches [49,50]. Furthermore, these AMX effects were still evident for at least two weeks after the AMX discontinuance although the resilient reductions of Klebsiella and human diseaserelated pathways were observed.…”

A Critical Evaluation of In Vitro Hesperidin 2S Bioavailability in a Model Combining Luminal (Microbial) Digestion and Caco‐2 Cell Absorption in Comparison to a Randomized Controlled Human Trial

“…A second adaptation may be the prolonged incubation of the Caco‐2 cells with the (poly)phenolic containing SHIME matrix to a point where a more true‐to‐life in vitro bioavailable profile is obtained, which should be feasible since the cytotoxicity of the SHIME was verified over longer periods (>24 h). With respect to this adaptation, we should also consider that previous research with poly(phenols) and peptides in a similar combined SHIME/Caco‐2 cell transport model, in which samples were taken at more time points than in this study, has demonstrated that the bioactives did not follow linear kinetics, which was assigned to interfering compounds from the digestive matrix …”

“…First, the potential of the microbial community to metabolize hesperidin under fed and fasted conditions was investigated using batch incubations (Supporting Information Figures 1 and 2). Next, two units of the SHIME (ProDigest, Belgium) were operated in parallel (TWINSHIME) as described elsewhere . Each setup consisted of five double‐jacketed, constantly stirred vessels at 37 °C under anaerobic conditions, simulating stomach; small intestine (SI); and ascending (AC), transverse (TC), and descending colon (DC).…”

“…To ensure optimal quality of the Caco‐2 cells when combined with the SHIME matrix, different dilutions (1:5, 1:10, 1:20 v/v) of SHIME digests from AC, TC, and DC, were used to treat 21‐d old Caco‐2 cell monolayers in 96‐well plates for 1 and 3 d. SHIME digests were centrifuged (3000 g , 10 min), and supernatants were filter sterilized. Mitochondrial respiration (MTT) and protein content (SRB) assays were applied as described before . Based on these assays (Supporting Information Figure 4), a non‐toxic dilution of 1:10 of SHIME matrix in serum‐ and phenol‐free medium was chosen for transport assays.…”

“…Recently, a combination model was developed in which the simulator of the human intestinal microbial ecosystem (SHIME), including small intestinal and colon digestion, was combined with Caco‐2 cell absorption to simulate intestinal absorption of bioactives in a food and digestive matrix–relevant context. This approach was applied for pomegranate and Aronia (poly)phenols . Although the relevance of this model was discussed based on literature, a validation with a parallel human bioavailability study was not described yet.…”