Fecal microbiota transplantation derived from Alzheimer's disease mice worsens brain trauma outcomes in young C57BL/6 mice

Traumatic brain injury causes neuroinflammation and neurodegeneration, which increase the risk and accelerate the progression of Alzheimer disease. The gut microbiome is an essential modulator of the immune system, impacting in the brain. AD has been related with reduced diversity and alterations in the community composition of the gut microbiota. This study aimed to determine whether the gut microbiota from AD mice exacerbates neurological deficits after TBI in young control mice. We prepared fecal microbiota transplants from 18 to 24 months old mice and from healthy controls. FMTs were administered orally to young mice after they underwent controlled cortical impact, as model of TBI. Then, we characterized the microbiota composition of the mice fecal samples by full length 16S rRNA sequence analysis. We collected the blood, brain, and gut tissues for protein and immunohistochemical analysis.