By Irene Zorraquín-Peña, Alba Tamargo, Dolores González de Llano, Begoña Bartolomé and M. Victoria Moreno-Arribas
Wine is considered one of the foods with the highest content of polyphenols, to which the health effects associated with moderate consumption of wine are mainly attributed. Although the greatest accumulation of polyphenols and phenolic metabolites (i.e., microbial-derived metabolites) takes place at the intestinal level, studies on the effects of wine on human digestive function and health are still scarce.
The colon lumen harbours metabolites resulting from food fermentation, the inhabitant microbiota and colonic cells. Gut microbiota enable the metabolism of both dietary and endogenous substrates to be used by the host, but microbial-derived metabolites can also modulate the immune system through impacting on the physiology and gene expression of host cells. As an approach to studying the role of colonic metabolites inside the lumen, researchers have been working with what it is called “faecal water”, which is the aqueous phase obtained after faeces ultracentrifugation. The faecal water contains a range of metabolites derived from dietary sources that might be implicated in the initiation and/or development of colorectal cancer, such as bile acids, fatty acids, N-nitroso compounds and heterocyclic amines. But it also contains compounds that are potentially beneficial, including short-chain fatty acids (SCFAs) and polyphenols.
The rationale behind this approach is that components of the faecal water are more likely to exert their effects on the colonic mucosa than substances bound to insoluble food residues or colonic bacteria. Moreover, several studies have demonstrated that the faecal water is cytotoxic (at certain extend) to mammalian cells in culture, and, based on this, “faecal water cytotoxicity” has been considered as a parameter of gut health.
The determination of the “faecal water cytotoxicity” is based on cell culture using human colon cell lines such as HT-29 or HCT 116. Briefly, after collection of faeces, the faecal water is separated by ultracentrifugation. Then, it was incubated with human colon cells previously conditioned. After a time, the cells were assayed for their viability (this is to say, their survival) by a test known as MTT. The high cell viability percentage (%), the less toxic the faecal water is.
The question is: Does wine consumption favourably modify the composition of the faecal water and, therefore, reduce its potential toxicity against colon cells?
We have tried to answer this question through a recent study at the frame of our current investigations about wine consumption and intestinal health. Concretely, the aim of this study was to assess the changes in the biomarker “faecal water cytotoxicity” after a wine nutritional intervention in healthy volunteers. For that, we carried out an intervention study with healthy volunteers consisted in two consecutive periods: (1) an initial washout period of 2 weeks during which the volunteers did not consume wine or any other alcoholic beverage and followed a diet low in polyphenols; and (2) a period of 4 weeks during which case volunteers (n=8) consumed a daily intake of red wine (250 mL/two doses), and control volunteers (n=3) kept to the low-polyphenol diet without wine consumption. Faecal samples were collected before and after the wine intervention period.
After assaying all faecal samples for their toxicity against two cell lines (HT-29 and HCT 116), we found that for the volunteers that consumed red wine, the toxicity of their faecal water was lower (higher % cell viability) after the red wine intervention (tfinal) than before the red wine intervention (tinitial). In contrast, for the volunteers that did not consume red wine (control group) no significant differences were found in the toxicity of their faecal water before and after red wine intervention.
Our results from both HT-29 and HCT 116 cell models showed that consumption of red wine (250 mL/day) over a period of 4 weeks led to a significant reduction in faecal water cytotoxicity, although this effect is individual-dependent. To the best of our knowledge, this is the first study to report data on faecal water cytotoxicity after the intake of wine or wine-related products in humans.
Therefore, the answer to our previous question is: Yes, moderate red wine consumption might modify the luminal metabolite content in such a way that it resulted in lower “faecal water cytotoxicity”, a parameter indicative of improved intestinal heath.
See more about these findings in: https://www.mdpi.com/2072-6643/12/9/2716
The authors of this study, Irene Zorraquín-Peña (PhD student), Alba Tamargo (PhD student), Dolores González de Llano (Senior Researcher), Begoña Bartolomé (Senior Researcher) and M. Victoria Moreno-Arribas (Senior Researcher) belongs to the Group of Wine Applied Biotechnology at the Institute of Food Science Research (CIAL, CSIC-UAM) in Madrid (Spain). The group’s activity is included within the areas of knowledge of wine microbiology, molecular biology, biochemistry, nutrition, advanced instrumental analysis, flavour chemistry and sensory analysis, and includes technical and complementary approaches, which involve from pure microorganisms to animal testing and experimentation intervention studies in humans, through cellular and gastrointestinal simulation technologies.
The group also collaborates with the simgi® (Dynamic Gastrointestinal Simulator Platform) at CIAL: https://www.cial.uam-csic.es/en/we-offer/simulador-gastrointestinal/
Some of our last wine-related publications are:
Esteban-Fernández, A.; Ibañez, C.; Simó, C.; Bartolomé, B.; Moreno-Arribas, M.V. (2020) Metabolome-based clustering after moderate wine consumption. OENO One, 3, 455-467, https://doi.org/10.20870/oeno-one.2020.54.3.2983
Zorraquín-Peña, I.; Sánchez-Hernández, E.; Ayuda-Durán, B.; Silva, M.; González-Paramás, A. M.; Santos-Buelga, C.; Moreno-Arribas M.A.; Bartolomé, B. (2020) Current and future experimental approaches in the study of grape and wine polyphenols interacting gut microbiota. J. Sci. Food Agric., 100, 3789–3802, https://doi.org/10.1002/jsfa.10378
Gil-Sánchez, I.; Cueva C.; Tamargo, A.; Quintela, J. C.; De La Fuente, E.; Walker, A.; Moreno-Arribas M.A.; Bartolomé, B. (2020) Application of the dynamic gastrointestinal simulator (simgi®) to assess the impact of probiotic supplementation in the metabolism of grape polyphenols. Food Res. Intern., 129, 108790, https://doi.org/10.1016/j.foodres.2019.108790
Taladrid, D.; Laguna, L.; Bartolomé, B.; Moreno-Arribas M.A. (2020) Plant-derived seasonings as sodium salt replacers in food. Trends Food Sci. Techn., 99, 194-202, https://doi.org/10.1016/j.tifs.2020.03.002
See more about our group in: https://www.cial.uam-csic.es/investigacion-e-innovacion/departamentos/departamento-de-biotecnologia-y-microbiologia-de-alimentos/grupo-de-biotecnologia-enologica-aplicada-bea/