Faecal matters How transplanting gut bacteria and their viruses impacts cardiometabolic disease

This thesis explores the potential of the gut microbiota in cardiometabolic diseases (CMD), a growing global health concern.
The first part focuses on faecal microbiota transplantation (FMT) as potential treatment for CMD. FMT is increasingly used as experimental treatment for diseases beyond recurrent Clostridioides difficile infections (rCDI). However, recruitment and screening of stool donors is challenging and costly, while there is a significant underuse of FMT in treating rCDI. Besides being an interesting treatment modality, FMT offers the opportunity to study the interaction between the gut microbiota and human host. A clinical trial shows that FMT-induced microbiota shifts alter miRNA expression. Additionally, FMT can be used to identify new beneficial microbes, like Anaerobutyricum soehngenii, which may replace FMT in the future due to its logistical challenges and potential safety risks.
In the second part, bacteriophages in CMD, particularly metabolic syndrome (MetSyn), are explored. Gut viromes in MetSyn and healthy controls reveal differences in viral richness, diversity, and viral cluster abundance. Since phages can modify bacterial communities, modulation of the gut microbiota using a faecal filtrate transplantation (FFT) is investigated in a pilot study. While FFT is safe, its impact on glucose metabolism is limited, emphasizing the need for better-defined phage consortia and matched donor-recipient pairs.
In conclusion, this thesis underscores the gut microbiota's potential in CMD and paves the way for more personalized, well-characterized cultured bacteria or phages as future avenues for improving human health.