title: Effects of periodontitis on aortic insulin resistance in an obese rat model.
abstract: The combination of obesity and its associated risk factors, such as insulin resistance and inflammation, results in the development of atherosclerosis. However, the effects of periodontitis on atherosclerosis in an obese body remain unclear. The aim of the study was to investigate the effects of ligature-induced periodontitis in Zucker fatty rats on initiation of atherosclerosis by evaluating aortic insulin resistance. Zucker fatty rats (n=24) were divided into two groups. In the periodontitis group, periodontitis was ligature-induced for 4 weeks, whereas the control group was left unligated. After the 4-week experimental period, descending aorta was used for measuring the levels of lipid deposits, immunohistochemical analysis, and evaluation of gene expression. Levels of serum C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-alpha), and insulin were also measured. Rats in the periodontitis group had significantly enhanced lipid deposits in the aorta, but not in the control group. Expression of suppressor of cytokine signaling 3, vascular cell adhesion molecule 1, reactive oxygen species, nitrotyrosine, and endothelin-1 in the periodontitis group was more intense than that in the control group. Significantly decreased levels of phosphatidylinositol 3-kinase (Pi3k) catalytic beta-polypeptide (Pi3kcb), Pi3kp85, and insulin receptor substrate 1 and 2 were observed in the periodontitis group. Levels of serum CRP and TNF-alpha were significantly increased in the periodontitis group. Under insulin-stimulated conditions, aorta in the periodontitis group altered the Akt phosphorylation. Periodontitis in obesity induced the initial stage of atherosclerosis and disturbed aortic insulin signaling.
authors.affiliation: Department of Preventive Dentistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Ekuni
authors.forename: Takaaki
authors.initials: T
authors.lastname: Tomofuji
authors.forename: Koichiro
authors.initials: K
authors.lastname: Irie
authors.forename: Kenta
authors.initials: K
authors.lastname: Kasuyama
authors.forename: Michihiro
authors.initials: M
authors.lastname: Umakoshi
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Azuma
authors.forename: Naofumi
authors.initials: N
authors.lastname: Tamaki
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Sanbe
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Endo
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Nishida
authors.forename: Manabu
authors.initials: M
authors.lastname: Morita
mesh_terms: D000818:Animals; D001011:Aorta / Q000378:metabolism*; D050197:Atherosclerosis / Q000209:etiology* / Q000378:metabolism; D019332:Endothelin-1 / Q000378:metabolism; D020869:Gene Expression Profiling; D007333:Insulin Resistance; D008026:Ligation; D008297:Male; D009765:Obesity / Q000150:complications* / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010518:Periodontitis / Q000150:complications* / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D051381:Rats; D011924:Rats, Zucker; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D019332:Endothelin-1; D019010:Vascular Cell Adhesion Molecule-1; D042461:Vascular Endothelial Growth Factor A; D019869:Phosphatidylinositol 3-Kinases; D051057:Proto-Oncogene Proteins c-akt