It is already known that the gut microbiome influences brain health including how the brain recovers from stroke, with previous research showing that a stroke alters the gut microbiota composition and microbiota dysbiosis has a substantial impact on stroke outcome.
Yet the role of SCFAs, a fermentation product from the bacteria in our guts known to impact microbiome health, in stroke recovery has not previously been explored.
The study
Researchers from the Ludwig-Maximilians-University Hospital in Munich, Leiden University Medical Center in The Netherlands, and the Southwestern Medical Center in Dallas, added short chain fatty acids to the drinking water of mice for four weeks before inducing a stroke.
The study report, recently published in JNeurosci, states that the mice that drank the fatty acid water experienced a better stroke recovery compared to the control mice, including reduced motor impairment and increased spine growth on dendrites—a crucial memory structure.
Additionally, the fatty acid-supplemented mice expressed more genes related to microglia, the brain's immune cells. Microglia activity could be responsible for increasing dendritic spines and improving stroke outcome. The study authors note that this relationship indicates short chain fatty acids may serve as messengers in the gut-brain connection by influencing how the brain responds to injury.
The report concludes: "Here, we demonstrate that SCFAs are potent and pro-regenerative modulators of post-stroke neuronal plasticity at various structural levels. We identified that this effect was mediated via circulating lymphocytes on microglial activation. These results identify SCFAs as a missing link along the gut-brain axis and as a potential therapeutic to improve recovery after stroke."
Source: The Journal of Neuroscience
Rebecca Sadler et al
“Short-chain fatty acids improve post-stroke recovery via immunological mechanisms”