title: Nitrogen dioxide air pollution near ambient levels is an atherogenic risk primarily in obese subjects: a brief communication.
abstract: Ambient exposure to nitrogen dioxide, a critical air pollutant in developed countries, is positively associated with cardiovascular mortality and morbidity. Although its cardiovascular effects are predominantly shown in patients with high risk of atherogenesis, no studies have elucidated whether daily exposure to nitrogen dioxide air pollution enhances atherogenic metabolisms, primarily in obese subjects who are susceptible to atherogenesis and subsequent cardiovascular diseases. We used male Otsuka Long-Evans Tokushima Fatty (OLETF) rats as obese subjects and Long-Evans Tokushima (LETO) rats as nonobese controls. The animals were continuously exposed to nitrogen dioxide at a concentration of 0, 0.16, 0.8, or 4.0 ppm from 8 weeks of age through 32 weeks. At 40 weeks of age, levels of body weight, triglyceride, and total cholesterol were significantly greater in the OLETF rats than in the LETO rats. A ratio of high-density lipoprotein (HDL) to total cholesterol was significantly smaller in the former than in the latter. In the LETO rats, nitrogen dioxide exposure significantly decreased only the levels of HDL as compared with clean air exposure. In the OLETF rats, however, nitrogen dioxide exposure at a concentration of 0.16 ppm significantly elevated triglyceride concentration and decreased the ratio of HDL to total cholesterol as well as the levels of HDL. Nitrogen dioxide air pollution near ambient levels is an atherogenic risk primarily in obese subjects.
authors.affiliation: Pathophysiology Research Team, National Institute for Environmental Studies, Tsukuba 305-0053, Japan. htakano@nies.go.jp
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Takano
authors.forename: Rie
authors.initials: R
authors.lastname: Yanagisawa
authors.forename: Ken-ichiro
authors.initials: K
authors.lastname: Inoue
authors.forename: Akinori
authors.initials: A
authors.lastname: Shimada
authors.forename: Takamichi
authors.initials: T
authors.lastname: Ichinose
authors.forename: Kaori
authors.initials: K
authors.lastname: Sadakane
authors.forename: Shin
authors.initials: S
authors.lastname: Yoshino
authors.forename: Kouya
authors.initials: K
authors.lastname: Yamaki
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Morita
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Yoshikawa
mesh_terms: D000397:Air Pollution; D000818:Animals; D001161:Arteriosclerosis / Q000503:physiopathology*; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D002784:Cholesterol / Q000378:metabolism; D008076:Cholesterol, HDL / Q000378:metabolism; D006801:Humans; D019570:Inhalation Exposure; D008297:Male; D009585:Nitrogen Dioxide / Q000378:metabolism*; D009765:Obesity / Q000503:physiopathology*; D010083:Oxidants, Photochemical / Q000378:metabolism*; D051381:Rats; D020318:Rats, Long-Evans; D012307:Risk Factors; D014280:Triglycerides / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D008076:Cholesterol, HDL; D010083:Oxidants, Photochemical; D014280:Triglycerides; D002784:Cholesterol; D009585:Nitrogen Dioxide