Multifunctional dietary approach reduces intestinal inflammation in relation with changes in gut microbiota composition in subjects at cardiometabolic risk: the SINFONI project

Abstract

The development of cardiometabolic (CM) diseases is associated with chronic low-grade inflammation, partly linked to alterations of the gut microbiota (GM) and reduced intestinal integrity. The SINFONI project investigates a multifunctional (MF) nutritional strategy's impact combining different bioactive compounds on inflammation, GM modulation and CM profile. In this randomized crossover-controlled study, 30 subjects at CM-risk consumed MF cereal-products, enriched with polyphenols, fibers, slowly-digestible starch, omega-3 fatty acids or Control cereal-products (without bioactive compounds) for 2 months. Metabolic endotoxemia (lipopolysaccharide (LPS), lipopolysaccharide-binding protein over soluble cluster of differentiation-14 (LBP/sCD14), systemic inflammation and cardiovascular risk markers, intestinal inflammation, CM profile and response to a one-week fructose supplementation, were assessed at fasting and post mixed-meal. GM composition and metabolomic analysis were conducted. Mixed linear models were employed, integrating time (pre/post), treatment (MF/control), and sequence/period. Compared to control, MF intervention reduced intestinal inflammation (fecal calprotectin, p = 0.007) and endotoxemia (fasting LPS, p < 0.05), without alteration of systemic inflammation. MF decreased serum branched-chain amino acids compared to control (p < 0.05) and increased B.ovatus, B.uniformis, A.butyriciproducens and unclassified Christensenellaceae.CAG-74 (p < 0.05). CM markers were unchanged. A 2-month dietary intervention combining multiple bioactive compounds improved intestinal inflammation and induced GM modulation. Such strategy appears as an effective strategy to target low-grade inflammation through multi-target approach.

Keywords: Polyphenols; branched chain amino-acids; cardiometabolic risk; endotoxemia; intestinal inflammation; omega 3.

Figure 1.

Figure 1: SINFONI Consort Flow Diagram

Figure 2.

MF intervention has reduced Calprotectin compared to control. Fecal fasting calprotectin was measured before and after 8-week treatment in at-risk subjects (n=30). Tukey box-plots (10-90 percentile) display the delta between the end and the beginning of the intervention (8 weeks); with blue lines refer to subjects who received the control intervention; orange lines refer to those who received MF intervention. A linear mixed model for repeated measures, with a compound symmetry structure as the covariance structure after Blom transformation, was used to determine whether the difference between the changes induced by 8-week MF intervention compared to Control were statistically significant. **p < 0.01.

Figure 3.

MF intervention has not significantly altered fasting systemic inflammation or cardiovascular-risk markers compared to control. Low-grade inflammation and cardiovascular risk markers were not significantly impacted by multifunctional intervention (n=30) compared to control.  Tukey box-plots (10-90 percentile) display the delta between before and after intervention (8 weeks); with blue lines refer to subjects who received the control intervention; orange lines refer to those who received MF intervention. A linear mixed model for repeated measures, with a compound symmetry structure as the covariance structure after Blom transformation, was used to determine whether the difference between the changes induced by 8-week MF intervention compared to Control were statistically significant.

Figure 4.

MF intervention reduces fructose-induced inflammation compared to control. Cardiovascular-risk markers were significantly reduced by multifunctional intervention (n=30) compared to control between after and before 1-week fructose challenge (delta between week 9 and 8). Tukey box-plots (10-90 percentile) with blue lines refer to subjects who received the control intervention; orange lines refer to those who received MF intervention. A linear mixed model for repeated measures, with a compound symmetry structure as the covariance structure after Blom transformation, was used to determine whether the difference between the changes induced by MF intervention compared to Control were statistically significant. *p < 0.05.

Figure 5.

MF intervention tend to reduce postprandial LBP/sCD14 excursions and reduce fasting endotoxemia (LPS) compared to control after 1-week fructose challenge. a) Post-prandial (total AUC between 0, 120 and 300 min) plasma LBP/sCD14 was measured in at-risk subjects (n=30) between the pre-intervention and 9-week periods. b) Fasting plasma LPS (ng/mL) was measured between the pre-intervention and 9-week periods. c) Post-prandial (total AUC between 0, 120 and 300 min) of LPS concentrations during the MF and control interventions between the pre-intervention and 9-week periods after ingestion of the standardized meal . Box-plot display the delta between the end of the intervention (after 8-week +1-week fructose) and before intervention. Tukey box-plots (10-90 percentile) with blue lines refer to subjects who received the control intervention; orange lines refer to those who received MF intervention. A linear mixed model for repeated measures, with a compound symmetry structure as the covariance structure after Blom transformation, was used to determine whether the difference between the changes induced by 9-week MF intervention compared to Control were statistically significant. *p < 0.05.

Figure 6.

MF intervention have increased beneficial gut microbiota species relative abundance (MSP) compared to control. Gut microbiota abundance was significantly impacted by multifunctional intervention (n=30). Histograms display the delta between the end of the intervention (after 8 weeks intervention) and before intervention. Tukey box-plots (10-90 percentile) with blue lines refer to subjects who received the control intervention; orange lines refer to those who received MF intervention. MSP: Metagenomic Species; p-values from Wilcoxon signed-rank test are displayed. *p < 0.05 **p <0.01 ***p <0.001

Figure 7.

MF intervention has modulated metabolomic profile evaluated by NMR technique (n=30). Box-plot display the delta between the end of the intervention (after 8 weeks intervention) and before intervention. Tukey box-plots with blue lines refer to subjects who received the control intervention; orange lines refer to those who received MF intervention. A linear mixed model for repeated measures, with a compound symmetry structure as the covariance structure after Blom transformation, was used to determine whether the difference between the changes induced by 8-week MF intervention compared to Control were statistically significant. *p < 0.05 **p <0.01.

Figure 8.

(a) Spearman’s rank correlation matrix between parameters significantly impacted by after MF intervention compared to control (b) A correlation network map depicting the Spearman’s correlation matrix was generated. Metabolites exhibiting high correlation were clustered together. The arrangement of metabolites was determined through multidimensional scaling of the absolute correlation values. Gradient color, line distance, and thickness were assigned to metabolite nodes based on correlation coefficients. Negative and positive correlations were represented by shades of red and blue, respectively. Stars (*) stand for correlations that are significant regarding p-values (p < 0.05).

Figure 9.

SINFONI Experimental design. In a randomized crossover study, participants were selected to assess the impact of MF intake on metabolic, inflammatory and gut microbiota parameters. Each participant underwent both the MF intervention and a control intervention in a randomized order, with a 6 to 8-week washout period between interventions to minimize carryover effects.