title: Periodontal bacteria aggravate experimental autoimmune myocarditis in mice.
abstract: Periodontitis is one of the most common infections in humans. Recently, published reports assert that periodontitis is associated with cardiovascular disease. Although it is said that viral, bacterial infections and autoimmune diseases may be the cause of myocarditis, the pathogenesis of it remains unclear. The aim of this study was to investigate the influence of a periodontal pathogen on experimental autoimmune myocarditis (EAM). Porphyromonas gingivalis (P.g.), PBS as a control, were injected into the mice. Histopathological and immunohistochemical analyses were performed. We examined heart mRNA levels using quantitative RT-PCR. The anti-P.g. IgG antibody level in plasma samples of the P.g.-injected group significantly increased compared with the PBS-injected group. Histopathological analysis detected that the myocarditis-affected areas and the fibrotic area in the P.g.-injected EAM group significantly increased compared with the PBS-injected EAM group (P < 0.05). Immunohistochemical analysis detected that more CD11b-positive cells were shown in the heart of the P.g.-injected EAM group compared with the PBS EAM-injected group (P < 0.05). Hearts from the P.g.-injected EAM group showed significantly increased expression of monocyte chemoattractant protein-1, IFN-γ, and matrix metalloproteinase-9 (MMP-9) mRNA compared with the hearts from the PBS-injected EAM group (P < 0.05). On day 7, serum levels of IL-6 were significantly enhanced in the P.g.-injected EAM group compared with the PBS-injected EAM group (P < 0.05). These results showed that P.g. injection could deteriorate EAM in mice through CD11b-positive cells, cytokines, and MMP-9 expression.
authors.affiliation: Department of Periodontology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Norihiko
authors.initials: N
authors.lastname: Ashigaki
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Suzuki
authors.forename: Masahito
authors.initials: M
authors.lastname: Ogawa
authors.forename: Ryo
authors.initials: R
authors.lastname: Watanabe
authors.forename: Norio
authors.initials: N
authors.lastname: Aoyama
authors.forename: Naho
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Tomoya
authors.initials: T
authors.lastname: Hanatani
authors.forename: Asuka
authors.initials: A
authors.lastname: Sekinishi
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Zempo
authors.forename: Yuko
authors.initials: Y
authors.lastname: Tada
authors.forename: Chisato
authors.initials: C
authors.lastname: Takamura
authors.forename: Kouji
authors.initials: K
authors.lastname: Wakayama
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Hirata
authors.forename: Ryozo
authors.initials: R
authors.lastname: Nagai
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Izumi
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Isobe
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood*; D001323:Autoantibodies / Q000097:blood*; D001327:Autoimmune Diseases / Q000453:epidemiology / Q000276:immunology* / Q000382:microbiology; D001835:Body Weight; D039481:CD11b Antigen / Q000276:immunology; D016207:Cytokines / Q000097:blood / Q000276:immunology; D004195:Disease Models, Animal; D008168:Lung / Q000276:immunology / Q000473:pathology; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000235:genetics / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D009205:Myocarditis / Q000453:epidemiology / Q000276:immunology* / Q000382:microbiology; D009218:Myosins / Q000276:immunology; D009929:Organ Size / Q000276:immunology; D010518:Periodontitis / Q000453:epidemiology / Q000276:immunology* / Q000382:microbiology; D016966:Porphyromonas gingivalis / Q000276:immunology*; D015995:Prevalence; D012307:Risk Factors; D016036:Seroepidemiologic Studies
chemical_list: D000907:Antibodies, Bacterial; D001323:Autoantibodies; D039481:CD11b Antigen; D016207:Cytokines; D020780:Matrix Metalloproteinase 9; C501830:Mmp9 protein, mouse; D009218:Myosins