Scientists have found tantalising clues that the devastating condition motor neurone disease may be linked to changes in microbes that live in the gut.
Studies in mice revealed that animals bred to develop amyotrophic lateral sclerosis (ALS), a form of the disease that affected the cosmologist Stephen Hawking, improved and lived longer when they were given an organism called Akkermansia muciniphila.
Among other substances, the microbe secretes a molecule called nicotinamide which may slow the course of motor neurone disease by improving the function of muscle-controlling neurons in the brain.
The findings are preliminary, and researchers stress that far more work is needed to confirm the effect. But as the first study to link gut microbes – collectively known as the microbiome – to the neurodegenerative illness, the work raises the possibility of new treatments for the condition.
Eran Elinav at the Weizmann Institute of Science in Israel began by showing that mice with a mutation common in ALS patients fared much worse when their gut microbes were all but wiped out with strong antibiotics. The finding suggested that somehow, microbes in the animals’ guts were involved in how quickly the disease progressed.
To explore further, the researchers analysed the gut microbes in the ALS-prone mice and compared them with normal mice. They spotted 11 strains of microbes that were either more or less common in the ALS-prone animals as the disease progressed and physical symptoms took hold.
Two types of bugs, called Ruminococcus torques and Parabacteroides distasonis, both exacerbated the symptoms of ALS, a disease that kills off motor neurons and tends to be fatal in humans within three to five years of diagnosis. Only Akkermansia muciniphila appeared to improve the animals’ symptoms.