Abstract: Polyphenols can reduce inflammation in the elderly by altering the intestinal microbiota and inducing the production of 3-propionic indole acid.
Source: University of Barcelona
The polyphenols in the foods we eat can prevent inflammation in the elderly as they alter the gut microbiota and induce the production of indole 3-propionic acid (IPA), a metabolite derived from tryptophan degradation due to intestinal bacteria.
This study, published in Molecular Nutrition and Food Research, has been carried out by the Biomarkers and Nutritional and Food Metabolomics Research Group of the Faculty of Pharmacy and Food Sciences of the University of Barcelona and CIBER on Fragility and Healthy Aging ( CYBERFES).
The team, led by Professor Cristina Andrés-Lacueva, from the UB’s Faculty of Pharmacy and Food Sciences, is also a member of the Catalan Food Innovation Network (XIA).
Polyphenols and healthy aging
Polyphenols are natural compounds, considered probiotics, that we eat mainly through fruits and vegetables. Various dietary polyphenols have known antioxidant and anti-inflammatory properties and the ability to interact with bacteria present in the human gut and produce postbiotics (such as IPA), which increases their positive health effects.
There is growing evidence that regular consumption of polyphenols in the diet can contribute to healthy aging, especially if they are part of a healthy diet, such as the Mediterranean, and are associated with a healthy lifestyle. that is, it includes regular physical activity and excluding tobacco and alcohol, for example.
The study shows that the interaction between polyphenols and the intestinal microbiota can induce the proliferation of bacteria with the ability to synthesize beneficial metabolites, such as IPA. IPA is a postbiotic with antioxidant, anti-inflammatory and neuroprotective properties that help improve the health of the intestinal wall. This compound appears to contribute to the prevention of some diseases associated with aging.
“If we consider the beneficial effects of IPA on the intestinal microbiota and overall health, it is important to find reliable strategies to promote the production of this metabolite,” said the study’s co-lead author, Tomás Meroño. , of the Department. of Nutrition, Food Sciences and Gastronomy at the UB and CIBERFES.
As part of the study, researchers performed a multivariate analysis to monitor serum IPA levels. The researchers analyzed the composition of the gut microbiota in fecal samples from fifty-one volunteers over the age of sixty-five who followed a diet rich in polyphenols (including consuming green tea, dark chocolate, fruits such as apples, pomegranates, and blueberries). for eight weeks.
Increased IPA in the blood and bacterial growth
The results show that the polyphenol-rich diet resulted in a significant increase in blood IPA levels, along with a decrease in levels of inflammation and changes in intestinal bacteria of the order Bacteroidales.
Polyphenols are natural compounds, considered probiotics, that we eat mainly through fruits and vegetables. The image is in the public domain
Surprisingly, the researchers did not observe the same effects in volunteers with kidney disease. This could be explained by the altered composition of its intestinal microbiota. These individuals showed lower amounts of IPA at the start of the trial compared to volunteers with normal renal function.
“These results could be clinically relevant, as low levels of IPA have been associated with a rapid decline in kidney function and chronic kidney disease,” says Professor Cristina Andrés-Lacueva.
Therefore, a polyphenol-rich diet, which includes probiotic foods such as green tea, dark chocolate, and some fruits such as apples, pomegranates, and blueberries, could increase IPA production through changes in the composition of the gut microbiota. . This increase in levels of a postbiotic such as IPA in the elderly could be beneficial in delaying or preventing chronic diseases that impair quality of life.
The study also includes the participation of teams from the University of Milan (Italy), Quadram Institute (UK) and the National Institute of Health and Aging Sciences (INCRA, Italy), among other institutions.
About this diet and inflammation research news
Author: Rosa MartínezSource: University of BarcelonaContact: Rosa Martínez – University of BarcelonaImage: The image is in the public domain
See also
Original research: open access. “A diet rich in polyphenols increases the metabolite of the intestinal microbiota indole 3-propionic acid in older adults with preserved renal function” by Tomás Meroño et al. Molecular nutrition and food research
Summary
A polyphenol-rich diet increases the metabolite of the intestinal microbiota indole 3-propionic acid in older adults with preserved renal function
Scope
Dietary polyphenols can alter the gut microbiota (GM) and promote the production of bioactive metabolites. Several indoles resulting from the transgenic metabolism of dietary tryptophan have been associated with intestinal barrier integrity. Our goal is to study changes in transgenic-derived indoles during a polyphenol-rich diet (PR) intervention in older adults.
Methods and results
Randomized, controlled, crossover trial in adults ≥ 60 years of age living in a residential care setting during an 8-week PR diet versus control (n = 51). Seven GM-tryptophan metabolites are measured in serum and a metataxonomic analysis of GM in fecal samples is performed.
Exploratory subgroup analyzes are performed based on renal function (RF). The PR diet significantly increases serum indole 3-propionic acid (IPA) in subjects with normal RF, but not in subjects with impaired RF. Other transgenic tryptophan metabolites are not affected.
Comparison of the initial GM composition shows changes in members of the order Bacteroidales, as well as a greater abundance of Clostridiales in participants with normal RF. During the assay, variations in IPA are associated with changes in C-reactive protein (β = 0.32, p = 0.010) and GM, particularly with Clostridials (r = 0.35, p <0.001). and Enterobacterials (r = −0.15, p). <0.05) orders.
Conclusion
A PR diet increases the serum concentration of IPA in older adults with normal RF. Our findings may be important in defining appropriate dietary interventions for the elderly.