Project properties
Title Gut-brain health effects in elderly
Group Human Nutrition and Health
Project type thesis
Credits 36
Supervisor(s) Yannick Vermeiren, Kirsten Kruger & Mara van Trijp
Examiner(s) Renger Witkamp
Contact info yannick.vermeiren@wur.nl
Begin date 2024/02/01
End date 2024/08/31
Description Prevention of cognitive decline by improving gut-health?
The potential role of disturbed intestinal health and microbiota community in the development of a wide range of chronic diseases is increasingly acknowledged. Growing evidence indicates an important role of intestinal health in the development of cognitive decline in ageing. The intestinal microbiome has an increasingly recognized impact on brain health and cognitive functioning. For instance, via the production of microbial metabolites, modulation of immune signaling, affecting the stress axis, and transmission via the vagus nerve. Furthermore, an impaired intestinal integrity, a so-called ‘leaky gut’, may result in the transfer of pathogenic or noxious compounds over the intestinal membrane into the body. As a consequence, disease development can be induced locally in the intestine but also at remote locations like the brain. Certain dietary fibres (potential prebiotics) have been shown to improve gut health and could have effects on brain function as a result.

Intervention trials in the elderly
In your thesis project, you will contribute to the execution of the PRECODE (Gut-brain health effects of PREbiotics in older adults with suspected COgnitive DEcline) study. This study starts early 2024. In PRECODE we will evaluate the gut- and brain health effects of 26 weeks of supplementation of three different dietary fibres (resistant dextrin, inulin and a seaweed polysaccharide) versus a placebo in elderly with Subjective Cognitive Decline plus (SCD+). The main outcome is to evaluate the effect of these dietary fibres on working memory, that we will measure by functional MRI at the Ziekenhuis Gelderse Vallei (ZGV) in Ede.

For the data analysis part of your thesis project, you will receive data from either the HELI-study or the COMBI-study, both part of the MOCIA consortium. These studies are currently at the end stage of completion, and have also evaluated the effects of interventions on the gut-brain axis in elderly:
• HELI consists of a 26-weeks multi-domain lifestyle intervention;
• COMBI consists of a 6-weeks colon-delivered multivitamin supplementation intervention.

Key words: human trials, elderly subjects, lifestyle, supplementation, gut health, gut-brain axis, microbiota, dietary fibre, subjective cognitive decline

Study tasks and data analysis
For PRECODE you will be involved with trial execution. This includes screening and follow-up telephone calls with participants, assisting with preparation for study visits on site at Wageningen University and ZGV. On the study visit days you will be involved (amongst others) with: Performance of neuropsychological tests batteries, help with processing of biofluids (blood, urine and faeces), assistance at fMRI study visits. For the HELI/ COMBI data analysis part, you will have your own gut-health topic with markers such as faecal characteristics (pH, water content, stool consistency, transit time), intestinal inflammation (calprotectin, β-defensins, sIgA), microbiota and fungi composition, metabolite analysis (SCFAs).

Used skills
Requirements MNH-B or MNH-C or MNH-F.