title: The periodontal pathogen Aggregatibacter actinomycetemcomitans affects experimental autoimmune myocarditis in mice.
abstract: Recent reports assert that dental health is linked to an increased risk of cardiovascular disease. It is well known that Aggregatibacter actinomycetemcomitans (A.a.) is highly associated with heart disease. Indeed, we previously reported that A.a. affects the development of heart disease in a mouse model. However, no reports have clarified the relationship between A.a. and experimental autoimmune myocarditis (EAM). The aim of this study was to investigate the effects of A.a. on EAM in mice. EAM was induced via the injection of cardiac myosin into the mice. A.a. or PBS was then injected into the mice using a chamber implanted into the back of each mouse. The weight of the organs and echocardiograms were obtained and a pathological analysis and quantitative RT-PCR were performed. Echocardiography showed that no statistical difference was observed between the two groups. A histopathological analysis demonstrated that the number of areas affected by myocarditis in the A.a.-injected EAM group was significantly increased compared to that observed in the PBS-injected EAM group (P < 0.05). The hearts of the mice in the A.a.-injected EAM group exhibited significantly increased expressions of MMP-9 mRNA compared to the hearts of the mice in the PBS-injected EAM group (P < 0.05). These results show that A.a. aggravated EAM via an enhanced MMP expression.
authors.affiliation: Department of Periodontology, Graduate School of Medical and Dental, Sciences Tokyo Medical and Dental University.
authors.forename: Norihiko
authors.initials: N
authors.lastname: Ashigaki
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Suzuki
authors.forename: Norio
authors.initials: N
authors.lastname: Aoyama
authors.forename: Masahito
authors.initials: M
authors.lastname: Ogawa
authors.forename: Ryo
authors.initials: R
authors.lastname: Watanabe
authors.forename: Naho
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Issei
authors.initials: I
authors.lastname: Komuro
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Izumi
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Isobe
mesh_terms: D016976:Aggregatibacter actinomycetemcomitans; D000818:Animals; D001327:Autoimmune Diseases / Q000378:metabolism / Q000382:microbiology*; D004195:Disease Models, Animal; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000096:biosynthesis; D051379:Mice; D008807:Mice, Inbred BALB C; D009205:Myocarditis / Q000378:metabolism / Q000382:microbiology*; D016871:Pasteurellaceae Infections / Q000150:complications*
chemical_list: D020780:Matrix Metalloproteinase 9