SUMMARY: Short chain fatty acids (SCFAs) produced by gut bacteria influence the way microglia develop. This then affects the way synapses are pruned, myelination, and other aspects of brain development. There are three types of SCFAs: acetate, butyrate, and propionate. They each have different effects on both brain cells and colon cells. Researchers observed that patients with autism spectrum disorder had hypermyelinated brain cells in certain areas, meaning that the synapses had been under-pruned by microglia during development.
LESSON COMMENTS: If you’re teaching students about myelin sheaths and action potential, this is a great article to show how changes in myelination and synapse pruning could lead to changes in behavior. I would suggest students look up the behaviors displayed by patients with autism to see if it correlates with the changes in brain cells observed in this study.
Lebovitz, Y., Ringel-Scaia, V. M., Allen, I. C., & Theus, M. H. (2018). Emerging Developments in Microbiome and Microglia Research: Implications for Neurodevelopmental Disorders. Frontiers in immunology, 9, 1993. doi:10.3389/fimmu.2018.01993