Go with your gut: microbiota meet microglia

Abstract

Discovering the environmental factors that control microglia is key to understanding and managing brain health. A new study finds that microbiota in the gut are essential for regulating microglia maturation and activation.

Figure 1

Gut to brain communication regulates microglia. The typical morphology, territorial boundaries, and molecular profile of microglia observed in mice living in standard, clean housing conditions (SPF; mouse on the left) are changed in mice living in a GF environment (mouse on the right). Microglia of GF mice display extended processes that encroach on each others territories and a gene expression profile more akin to immature cells (e.g. upregulation of CSFR1 and Ddit4). Partial ablation of gut microbiota with antibiotics produced a microglia phenotype similar to the one observed in GF mice while recolonization of GF mice with defined ASF bacteria or feeding with SCFA normalized the microglial phenotype. ASF, altered Schaedler Flora; CSFR1, colony stimulating factor 1; Ddit4, DNA damage-inducible transcript 4; GF, germ free; SCFA, short-chain fatty acids; SPF, specific pathogen free.