title: Effects of angiotensin II type 1 receptor gene polymorphisms on insulin resistance in a Japanese general population: the Tanno-Sobetsu study.
abstract: Although gene polymorphisms in the renin-angiotensin system (RAS) are predisposing factors for cardiovascular diseases, the precise mechanisms and interactions among confounding factors have not been clarified. We investigated whether genetic variants of RAS are involved in insulin sensitivity in a Japanese general population. During a medical checkup in 2001, participants (n=550) were recruited from among the residents of the towns of Tanno and Sobetsu, and written informed consent was obtained to participate in the genetic analysis and the epidemiological study. The insertion/deletion (lID) polymorphism of the angiotensin-converting enzyme gene (ACE), the Met235Thr polymorphism of the angiotensinogen gene (AGT), and the A1166C polymorphism of the angiotensin II type 1 receptor gene (AGTR1) were determined by gel electrophoresis or the TaqMan PCR method. We assessed insulin sensitivity using the homeostasis model assessment insulin resistance (HOMA-IR). The RAS gene polymorphisms were not associated with log-transformed values of HOMA-IR, whereas borderline association (p=0.02) was found between the A1166C polymorphism and dichotomous categorization of insulin resistance (defined as HOMA-IR > or =1.73). Our results suggested that the A1166C polymorphism of AGTR1 might affect insulin resistance by altering the responsiveness to angiotensin II signaling, though this mechanism is as yet inconclusive. Further study is required to confirm these findings in a larger, multi-ethnic population.
authors: Department of Geriatric Medicine, Osaka University Graduate School of Medicine, Suita, Japan.
authors: Hiroshi
authors: H
authors: Akasaka
authors: Tomohiro
authors: T
authors: Katsuya
authors: Shigeyuki
authors: S
authors: Saitoh
authors: Ken
authors: K
authors: Sugimoto
authors: Yuxiao
authors: Y
authors: Fu
authors: Satoru
authors: S
authors: Takagi
authors: Hirofumi
authors: H
authors: Ohnishi
authors: Hiromi
authors: H
authors: Rakugi
authors: Nobuyuki
authors: N
authors: Ura
authors: Kazuaki
authors: K
authors: Shimamoto
authors: Toshio
authors: T
authors: Ogihara
mesh_terms: D000368:Aged; D044466:Asian People / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D011153:Population / Q000235:genetics; D044140:Receptor, Angiotensin, Type 1 / Q000235:genetics* / Q000502:physiology
chemical_list: D044140:Receptor, Angiotensin, Type 1