title: Porphyromonas gingivalis infection modifies oral microcirculation and aortic vascular function in the stroke-prone spontaneously hypertensive rat (SHRSP).
abstract: The functional modulation of vascular endothelial cells associated with stroke and periodontal disease has not yet been clarified. The objective of this study is to analyze the vascular endothelial function of periodontitis and stroke animal models. We examined endothelial function and gingival blood flow in oral microcirculation in vivo and measured the isometric tension in vitro of the aorta in animal models for lifestyle-related diseases, such as periodontitis and stroke. Gingival reactive hyperemia (GRH) was measured using laser Doppler flowmetry. Wistar Kyoto rats (WKY) were used as control animals; Porphyromonas gingivalis (P. gingivalis) infected WKY (WKY + Pg) as the periodontitis model; stroke-prone spontaneously hypertensive rat (SHRSP) as the stroke model; and a final group consisting of P. gingivalis infected SHRSP (SHRSP + Pg). Furthermore, for each group, the relaxation of descending aortic ring preparations was measured using a force transducer. The GRH was estimated by maximum response (peak), time taken for the maximum response to fall to one half (T1/2), and increased total amount of blood flow (mass). The relative change in T1/2 and mass increased in SHRSP + Pg compared to WKY. However, mass significantly increased in WKY (758.59 ± 88.21 ml/min/100 g s to 1755.55 ± 226.10 ml/min/100 g s) and SHRSP (1214.87 ± 141.61 ml/min/100 g s to 2674.32 ± 675.48 ml/min/100 g s) after treatment with acetylcholine. In addition, T1/2 and mass significantly increased in WKY + Pg (624.18 ± 96.36 ml/min/100 g s to 2629.90 ± 612.01 ml/min/100 g s) and SHRSP + Pg (1116.36 ± 206.24 ml/min/100 g s to 1952.76 ± 217.39 ml/min/100 g s) after treatment with nitroglycerin. Furthermore, the endothelium-dependent relaxation of ring preparations, evoked by acetylcholine, was attenuated in SHRSP compared with WKY, but not in SHRSP + Pg. This attenuation effect in SHRSP could be prevented by superoxide dismutase pretreatment. Our results suggest altered endothelial function may occur in gingival tissue in animal models experiencing both periodontitis and stroke. Therefore, these results indicate the disruption of vascular function in oral microcirculation may be caused by the interaction between the oxidative stress induced by periodontitis and nitric oxide in periodontitis, similar to the interactions present in stroke cases.
authors.affiliation: Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Seiko
authors.initials: S
authors.lastname: Funaki
authors.affiliation: Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Tokutomi
authors.affiliation: Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan. Electronic address: s.takahashi@kdu.ac.jp.
authors.forename: Satoko
authors.initials: S
authors.lastname: Wada-Takahashi
authors.affiliation: Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Yoshino
authors.affiliation: Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Ayaka
authors.initials: A
authors.lastname: Yoshida
authors.affiliation: Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Yojiro
authors.initials: Y
authors.lastname: Maehata
authors.affiliation: Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Chihiro
authors.initials: C
authors.lastname: Miyamoto
authors.affiliation: Division of Microbiology, Department of Infection Control, Graduate School of Dentistry, Kanagawa Dental University, Kanagawa, Japan.
authors.forename: Toshizo
authors.initials: T
authors.lastname: Toyama
authors.affiliation: Division of Microbiology, Department of Infection Control, Graduate School of Dentistry, Kanagawa Dental University, Kanagawa, Japan.
authors.forename: Takenori
authors.initials: T
authors.lastname: Sato
authors.affiliation: Division of Microbiology, Department of Infection Control, Graduate School of Dentistry, Kanagawa Dental University, Kanagawa, Japan.
authors.forename: Nobushiro
authors.initials: N
authors.lastname: Hamada
authors.affiliation: Yokosuka-Shonan Disaster Health Emergency Research Center & ESR Laboratories, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan.
authors.forename: Masaichi Chang-Il
authors.initials: MC
authors.lastname: Lee
authors.affiliation: Department of Oral Science, Graduate School of Dentistry, Kanagawa Dental University, 82 Inaoka-cho, Yokosuka, Kanagawa 238-8580, Japan. Electronic address: takahashi.shunsuke@kdu.ac.jp.
authors.forename: Shun-Suke
authors.initials: SS
authors.lastname: Takahashi
mesh_terms: D000818:Animals; D001011:Aorta / Q000503:physiopathology*; D016866:Bacteroidaceae Infections / Q000382:microbiology* / Q000503:physiopathology*; D001794:Blood Pressure; D004195:Disease Models, Animal; D006940:Hyperemia / Q000209:etiology; D008297:Male; D008833:Microcirculation; D010518:Periodontitis / Q000382:microbiology* / Q000503:physiopathology*; D016966:Porphyromonas gingivalis; D051381:Rats; D011918:Rats, Inbred SHR; D012039:Regional Blood Flow; D020521:Stroke / Q000209:etiology* / Q000503:physiopathology
keywords: Gingival blood flow; Gingival reactive hyperemia; Laser Doppler flowmetry; Periodontitis; Reactive oxygen species (ROS); Stroke-prone spontaneously hypertensive rat (SHRSP)