Relations between endothelial damage and oral bacteria

Abstract

We investigated cerebral hemorrhage 24 hours after MT8148 (MT), the standard strain of S. mutans or TM295 (TW) isolated from a subject with cerebral hemorrhage administered, using cerebral hemorrhage model in mice. Bacteria-induced aggravation of cerebral hemorrhage was observed in mice infected with TW, but not MT. The most important factor for highly virulent strains is the presence of the CBP expression. The reduction of cerebral hemorrhage was observed with TW295CND, a defect of CBP expression. TW caused the activation of MMP-9 in the ipsilateral hemisphere of injured mouse brain and reduced the platelet aggregation induced by collagen. S. mutans strains with collagen-binding protein possess high affinity to the exposed collagen fibers, resulting in the accumulation of highly virulent bacteria in collagen-denuded blood vessels. The accumulation of bacteria consequently leads to the activation of MMP-9 and the inhibition of platelet aggregation in injured blood vessels, resulting in an acceleration of bleeding and hemorrhagic infarction.