Fabiana Andrea Hoffmann Sardá

Non-nutritive sweeteners (NNSs) are popular sugar substitutes, valued for their potential to reduce caloric intake and associated health risks. However, their long-term effects on the human gut microbiome remain debatable. This study investigates the impact of tagatose, allulose, Rebaudioside-A (Reb-A), and saccharin on quorum-sensing (QS)-regulated phenotypes and gene expression in QS biosensor model bacteria. It sheds light on their potential influence on the gut microbiome. Our study revealed diverse effects among the NNSs. Tagatose and allulose demonstrated QS phenotypic inhibition in Chromobacterium violaceum (≈50%) and Pseudomonas aeruginosa (20–50%) in a concentration-dependent manner. Additionally, tagatose and allulose decreased the P. aeruginosa lasI gene expression. Reb-A and saccharin presented a significant, however less prominent, phenotypic inhibition on C. violaceum (25–30%) and P. aeruginosa swarming motility (≈20%). Both NNSs decreased the expression of the lasI gene of P. aeruginosa. Molecular docking of QS regulatory proteins showed that saccharin and Reb-A have significantly higher binding affinity compared to allulose and tagatose, relative to native inducers. These results suggest the complex interactions mediated by NNSs in QS regulatory pathways. These findings provide valuable insights into the varied, species and dose-dependent effects of NNS on microbial communication, suggesting potential implications for the gut microbiome.

Over the past two decades, our understanding of human gut microbiota composition and function has grown significantly. The surge in studies and data has unveiled the profound influence of gut microbiota on host nutrition, health, and behavior, bridging biology, medicine, and ecology. The dynamic interaction between daily choices, life events, and gut microbiota composition makes it a fascinating subject for scientists to communicate to diverse audiences. Effective scientific communication involves adapting the delivery of knowledge to different audiences, using precise language in academic settings and accessible concepts in public forums like science festivals or social media. With the growing interest in gut microbiota beyond academic circles, there is an increased risk of disseminating information lacking scientific rigor. This study aims to assess the general public’s knowledge about gut microbiota and evaluate healthcare professionals’ understanding of its links to various health conditions, ultimately informing better communication strategies for both groups.

OC63. Enhancing the acceptability of Stevia sweetened cookies through the addition of Inulin: A study on texture, chemical attributes, and taste | POSTER

Purpose of review: Glycemia goals are used as indicators of control and progression in prediabetes and diabetes. Adopting healthy eating habits is essential. It is worth considering the quality of carbohydrates to help with dietary glycemic control. The present article aims to review recent meta-analyses published in the years 2021–2022 on the effects of dietary fiber and low glycemic index/load (LGI/LGL) foods on glycemic control and how gut microbiome modulation contributes to glycemic control. Recent findings: Data involving more than 320 studies were reviewed. The evidence allows us to infer that LGI/LGL foods, including dietary fiber intake, are associated with reduced fasting glycemia and insulinemia, postprandial glycemic response, HOMA-IR, and glycated hemoglobin, which are more evident in soluble dietary fiber. These results can be correlated with changes in the gut microbiome. However, the mechanistic roles of microbes or metabolites implicated in these observations continue to be explored. Some controversial data highlight the need for more homogeneity between studies. Summary: The properties of dietary fiber are reasonably well established for their glycemic homeostasis effects, including the fermentation aspects. Findings of gut microbiome correlations with glucose homeostasis can be incorporated into clinical nutrition practice. Target dietary fiber interventions on microbiome modulation can offer options to improve glucose control and contribute to personalized nutritional practices.

The properties of each food, composition, and structure affect the digestion and absorption of nutrients. Dietary fiber (DF), especially viscous DF, can contribute to a reduction in the glycemic response resulting from the consumption of carbohydrate-rich foods. Target and control of postprandial glycemic values are critical for diabetes prevention and management. Some mechanisms have been described for soluble DF action, from the increase in chyme viscosity to the production of short-chain fatty acids resulting from fermentation, which stimulates gastrointestinal motility and the release of GLP-1 and PYY hormones. The postprandial glycemic response due to inulin and resistant starch ingestion is well established. However, other soluble dietary fibers (SDF) can also contribute to glycemic control, such as gums, β-glucan, psyllium, arabinoxylan, soluble corn fiber, resistant maltodextrin, glucomannan, and edible fungi, which can be added alone or together in different products, such as bread, beverages, soups, biscuits, and others. However, there are technological challenges to be overcome, despite the benefits provided by the SDF, as it is necessary to consider the palatability and maintenance of their proprieties during production processes. Studies that evaluate the effect of full meals with enriched SDF on postprandial glycemic responses should be encouraged, as this would contribute to the recommendation of viable dietary options and sustainable health goals.

In chronic kidney disease (CKD), the accumulation of gut-derived metabolites, such as indoxyl sulfate (IS), p-cresyl sulfate (pCS), and indole 3-acetic acid (IAA), has been associated with the burden of the disease. In this context, prebiotics emerge as a strategy to mitigate the accumulation of such compounds, by modulating the gut microbiota and production of their metabolites. The aim of this study was to evaluate the effect of unripe banana flour (UBF—48% resistant starch, a prebiotic) on serum concentrations of IS, pCS, and IAA in individuals undergoing peritoneal dialysis (PD). A randomized, double-blind, placebo-controlled, crossover trial was conducted. Forty-three individuals on PD were randomized to sequential treatment with UBF (21 g/day) and placebo (waxy corn starch—12 g/day) for 4 weeks, or vice versa (4-week washout). The primary outcomes were total and free serum levels of IS, pCS, and IAA. Secondary outcomes were 24 h urine excretion and dialysis removal of IS, pCS, and IAA, serum inflammatory markers [high-sensitivity C-reactive protein (hsCRP), interleukin-6 (IL-6), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α)], serum lipopolysaccharide LPS, and dietary intake. Of the 43 individuals randomized, 26 completed the follow-up (age = 55 ± 12 years; 53.8% men). UBF did not promote changes in serum levels of IS (p = 0.70), pCS (p = 0.70), and IAA (p = 0.74). Total serum IS reduction was observed in a subgroup of participants (n = 11; placebo: median 79.5 μmol/L (31–142) versus UBF: 62.5 μmol/L (31–133), p = 0.009) who had a daily UBF intake closer to that proposed in the study. No changes were observed in other secondary outcomes. UBF did not promote changes in serum levels of IS or pCS and IAA; a decrease in IS was only found in the subgroup of participants who were able to take 21g/day of the UBF.

High postprandial glycemia in the non-diabetic population is one of the known universal mechanisms for the progression of noncommunicable diseases (NCDs), which have impacted the finances of both individuals and of health systems. In order to highlight the role of carbohydrates in glycemic control and its implications on health, the International Life Sciences Institute Brazil held an international workshop on “Carbohydrates, Glycemia and Health”. Carbohydrate digestion rate is related to glycemic response, which mainly depends on the quality and amount of carbohydrate ingested, and thus it may be modulated by intrinsic and extrinsic factors. These effects can be verified by using different methods which evidence how physiology adapts in the uptake of glucose. Consumers can be aided with the knowledge/awareness of the benefits of high postprandial glycemia control in non-diabetic subjects. Multisectorial actions can contribute to decrease the onset and worsening of NCDs. A strategy indicated to the public in general to expand the availability of products that do not result in a sudden increase of postprandial plasma glucose and/or insulin would be to use alternative ingredients and/or technology in addition to making the legally allowed communication of benefits, which are supported by scientific studies.

Background - Bowel function is a widely evaluated parameter in interventional and longitudinal studies since it is associated with good maintenance of health. The evaluation of intestinal function has been performed by many questionnaires, however, there are few options validated in Brazilian Portuguese. Objective - The aim of this work was to translate and validate into Brazilian Portuguese the Gastrointestinal Symptom Rating Scale (GSRS) questionnaire. Methods - Translation and cultural adaptation were performed according to a previously established methodology followed by reliability calculations. Results - The final translated GSRS questionnaire showed an adequate value of overall reliability of Cronbach's alpha of 0.83, and its domains were classified from acceptable to adequate. The overall test-retest reliability by intraclass correlation coefficient (ICC) was 0.84, considered excellent. Conclusion - The GSRS was translated and validated into Brazilian Portuguese, with appropriate internal consistency and reliability and is available to be used in assessments of bowel function.