From the article:
Bacteria in the gut microbiome drive the formation of cerebral cavernous malformations (CCMs), clusters of dilated, thin-walled blood vessels in the brain that can cause stroke and seizures, according to new research published this week in Nature by researchers from the Perelman School of Medicine at the University of Pennsylvania. View full publication
One implication might also be that ameliorating intestinal permeability and/or reducing the activity of TLR4 (e.g. via hypermethylation of TLR4 from 5g/day of fish oil) might also protect against cerebrovascular disease through this mechanism.