Clinical Research Directory

Effects of Barley and Kefir on Gut Microbiota in Physically Active Adults

The purpose of this randomized controlled clinical trial is to investigate whether a four-week dietary intervention consisting of a daily meal with barley and kefir can influence gut microbiota diversity and composition in physically active adults participating in endurance sports. The study will further examine whether diet-induced changes in the gut microbiota are associated with changes in relevant circulating and urinary metabolites. Growing evidence indicates that the gut microbiota plays an important role in metabolism, immune function, and overall health. Dietary factors are among the most important modulators of gut microbial composition. Barley contains dietary fibre including beta-glucans and other prebiotic components that may promote the growth of beneficial bacteria, while kefir contains live probiotic lactic acid bacteria that may influence both microbial composition and function. However, there is limited knowledge regarding how practical and realistic dietary interventions affect gut microbiota and host biological responses in physically active adults. The primary objectives of the study are to determine whether daily consumption of a standardized meal consisting of barley porridge (70 g) and kefir (200 mL) for four weeks alters gut microbiota alpha diversity and gut microbiota composition compared with maintaining a habitual diet. Secondary objectives are to investigate whether changes in gut microbiota are associated with changes in circulating and urinary metabolite profiles related to gut microbiota activity and energy metabolism. Physically active participants aged 18 to 55 will be recruited and randomized to either an intervention group or a control group. Participants assigned to the intervention group will consume a daily breakfast consisting of barley porridge and kefir for four weeks. Participants assigned to the control group will maintain their habitual diet without receiving the dietary intervention. Both groups will be asked to maintain their usual dietary practices and training routines throughout the study period. Data collection will be performed at baseline and after four weeks and will include stool samples, blood samples, urine samples, dietary interviews, and recording of training volume and training load. Stool samples will be analyzed using Precision Microbiome Profiling (PMP) to characterize gut microbiota diversity and composition. Blood and urine samples will be analyzed using metabolomics approaches to assess circulating and urinary metabolites. The study aims to provide a comprehensive understanding of the relationships among diet, gut microbiota, metabolite profiles, and cellular responses in physically active adults, and to generate new knowledge regarding biological mechanisms that may be relevant for health, recovery, and physical performance.

Probiotic in Fruit Snack

The aim of this study is to investigate whether a fruit snack containing probiotic ''Lactobacillus rhamnosus'' can survive and establish itself more effectively in the gut when it is protected inside a natural plant-protein coating and delivered in a fruit snack. Lactobacillus rhamnosus is a beneficial bacterium that may support gut health and influence communication between the gut and the brain. In this study, we will examine how the probiotic affects the gut microbiome (the community of bacteria that naturally live in the gut). We are recruiting 25 healthy men and women aged 25-65 years with a body mass index (BMI) between 18.5 and 31.9 kg/m². Participants will be randomly assigned to receive either: A) Fruit snack containing encapsulated Lactobacillus rhamnosus probiotics, or a similar fruit snack that does not contain probiotics (placebo). Neither participants nor researchers (blinded) will know which snack is being provided during the study. Participants will attend four study visits over approximately 10 weeks (70 days): at the baseline visit Day 0 and again at Days 28, Day 42, and Day 70. A blood and stool samples will be collected at the beginning of the study, and samples will be used to assess changes in the gut microbiome over time. The findings from this study will help us better understand how targeted delivery of probiotics to the gut may influence the gut microbiome and support digestive health.

Sucralose and Glucose Metabolism in Young Healthy Adults

This study aimed to investigate the effects of a three-week consumption of sucralose-sweetened beverages (low-calorie sweetener) on postprandial glycemic responses in healthy adults, compared with sugar-sweetened beverages under real-world conditions. In brief, postprandial glycemic responses are used as an indicator of how your body manages blood sugar levels after consuming glucose. To explore potential mechanisms underlying any observed changes in postprandial glycemic responses, we further investigated potential alterations in gut microbiota composition and functionality, as well as plasmatic biomarkers of intestinal permeability and systemic low-grade inflammation. Finally, this project explored whether free sugars derived from a natural source (100% natural fruit juice) elicit metabolic responses that differ from those of refined sugars. Participants visited the laboratory for a preliminary screening session to assess eligibility prior to being randomly assigned to one of the three experimental groups consuming either sucralose-sweetened beverages (LCS), sucrose-sweetened beverages (SSB), or 100% natural fruit juice (FJ) at dosage approximating real-world consumption over three weeks. Participants underwent two experimental sessions (duration of 3 hours each) at the beginning and completion of the study as outlined below.

Effect of Rectal Administration of Breast Milk on Gut Microbiota in Preterm Infants

This study aims to evaluate the effect of rectal administration of maternal breast milk on gut microbiota development in preterm infants. Preterm infants are at increased risk of dysbiosis due to immaturity and limited enteral feeding in the early postnatal period. In this randomized controlled study, preterm infants will receive either rectal administration of maternal breast milk or normal saline. The primary objective is to compare gut microbiota composition between the two groups. The findings may provide insight into a novel and non-invasive strategy to support microbiota development in preterm infants.

Effects Of Dietary Fats on Gut Microbiota Composition and Metabolic Activity in Healthy Adults

This study will investigate how adding a specific type of dietary fat to daily meals for two weeks affects the gut bacteria and their activity. Participants will be randomly assigned to consume one of four types of fat: butter, coconut oil, olive oil, or sunflower oil (60 mL each day for 2 weeks). Stool and blood samples (after an overnight fast) will be collected at 3 time points during the study (Days 1, 7, and 22). These samples will be used to measure metabolites produced by gut bacteria, the types of bacteria present in the gut, blood lipids, and inflammatory markers. The study, based on previous in vitro findings, aims to understand whether different types of fats (based on their structure and level of saturation) have different effects on gut bacteria and their activity in healthy subjects.

The Effect of Vitamin C Supplementation on Gut Microbiota Composition and Function in Healthy Adults

The aim of this dietary intervention study is to explore how vitamin C affects the bacteria that live in our gut. Vitamins are essential nutrients found in fruits and vegetables. Our bodies cannot make them on their own, but we need them to function correctly. Vitamins play various roles, including supporting the immune system and assisting with energy production. Some vitamins in our diet can reach the large intestine, where they may be used by gut bacteria to promote their growth. In this study, we aim to investigate how our gut bacteria interact with vitamin C and how this interaction affects their growth and activity. For this study, participants will follow their habitual diet for one-week (run-in period), followed by two consecutive two-week supplementation periods in which they will first take a moderate dose (200 mg/day) and then a high-dose (1000 mg/day) of vitamin C. A final one-week period follow up period will involve a return to their habitual diet. Faecal, blood and urine samples will be collected at the start and end of each supplementation period to explore changes in gut microbiota composition, activity and markers of inflammation.

Monitoring the Clinical and Immunological Effects of Microbiome Changes Following Severe Burn Injury

The aim of this study is to longitudinally monitor dynamic changes in the gut microbiome following severe burn injury using fecal samples. Under standard nutritional protocols and intensive care management, serial fecal sampling is performed to assess alterations in microbiome diversity and composition, as well as the indirect effects of these changes on measurable inflammatory biomarkers, endocrine, hematological, immunological, and other organ-specific parameters, the clinical course, and patient outcomes.