Clinical trials

People living with obesity have a higher risk of late-life cognitive decline and developing dementia. In women, the risk of cognitive decline may further raise during the menopausal transition, a period of substantial hormonal and metabolic changes. Recent studies suggest that a healthy diet could help to prevent neurocognitive disorders by reducing inflammatory processes in the body and brain. Emerging evidence further indicates that the gut-brain axis and the intestinal microbiome play a crucial role in mediating this effect, through metabolic, immune, neuronal and vascular routes. Modifying the gut microbiota may thus counteract the heightened systemic inflammation seen in obesity and during menopausal transition to eventually benefit brain health. Specifically, plant-based nutirents, such as fibre and polyphenols, have microbiome-changing, anti-inflammatory and neuroprotective properties that may slow brain aging and neuro-inflammation. However, evidence from human interventional studies and knowledge on the underlying mechanisms remain scarce. This randomized controlled trial will therefore test whether altering gut bacteria through six months of daily intake of a personalized "polybiotic" dietary formula, compared to placebo, improves markers of brain health in women during the perimenopausal transition that are living with overweight or obesity. We plan to enroll 120 women aged 35-60 with overweight/obesity and elevated inflammatory blood markers, randomized to: intervention (7.5 or 15 g inulin, plus 200 mg resveratrol and 320 mg quercetin per day in powder form with main meals) or control (isocaloric maltodextrin). Exclusions include type 1 diabetes, current psychiatric/gastrointestinal disorders, and magentic resonance imaging (MRI) contraindications. Before and after 26 weeks, participants will undergo brain MRI to assess inflammation-related brain markers, neuropsychological testing, anthropometric measurements, they will fill in a set of questionnaires and donate stool and blood. Gut bacteria will be profiled by next-generation sequencing; metabolites will be measured in blood and stool. The primary outcome is a proxy of neuroinflammation in the white matter assessed using diffusion-weighted MRI. Secondary analyses will examine blood-brain-barrier permeability and other functional and structural MRI measures, including MR spectoscropy. Mechanistic links among changes in inflammatory markers, microbiota composition, and short-chain fatty acids will be explored using path and network models. This study may help to develop novel prevention and treatment strategies to mitigate obesity-related cognitive decline via the gut-brain axis.

The goal of the present clinical trial is to explore whether an innovative technology-based approach can help individuals who have had a stroke and can no longer move their hands with ease. Our approach consists of a combination of two technologies: Transcranial Magnetic Stimulation (TMS) and a Brain-Computer Interface (BCI). The former entails the application of magnetic fields over the head to stimulate the brain preparing it for a better ability to produce movement. The latter consists of measuring brain activity to personalize a type of computer-based training that is designed to increase communication between the brain and the muscles.

The investigators aim to test the hypothesis that a microbiome-changing dietary intervention improves food decision-making and to determine the underlying microbiotal and metabolic mechanisms. To this end, 90 overweight/obese adults will be enrolled in a randomized controlled trial to test the effects of a pre-biotic dietary intervention (supplementary intake of soluble fibre) or a behavioural lifestyle intervention (weekly educational program) vs. control condititon (supplementary intake of isocaloric starch) over a period of 26 weeks. Before and after the intervention/control period, participants will undergo task-based functional and structural MRI and cognitive testing. The gut microbiota will be assessed using 16S rDNA next-generation sequencing (V3/V4 region) in stool samples. Diet, anthropometry and lifestyle will be monitored with questionnaires and metabolomics will be assayed in peripheral blood and stool (e.g. SCFA). Using a modulation of gut-brain communication through a prebiotic diet and lifestyle intervention, respectively, the investigators will be able to discover microbiota communities that play a key role for eating behaviour. Related mechanistic insights could help to develop novel preventive and therapeutic options to combat unhealthy weight gain in our obesogenic society.