The effect of probiotics on the ageing nervous system

Probiotics are live bacteria which carry many beneficial effects to the host and have been shown to play a role in preventing or treating diseases, with most being linked to the gastrointestinal tract and dysbiosis. Dysbiosis of the microbiome refers to an imbalance in the gut microbial community and is associated with ageing and disease. In this study the nematode worm C. elegans is used to examine whether probiotics have an effect on health and ageing, with a focus on the ageing nervous system. We focus on Alzheimer's disease (AD) and Parkinson's disease (PD) models, whereby human Aß and α-synuclein are expressed in muscle. This study focuses closely on the probiotic strains, L. rhamnosus ROO11 and L. rhamnosus HA-111. ROO11 and HA-111 significantly delayed the rate of paralysis in Aß transgenic C. elegans p38 MAPK pathway. Furthermore, this study also suggests that these probiotic strains have the ability to form biofilms, potentially having many benefits, which were not discussed in this thesis, such as increasing lifespan and pathogen resistance.