[Relationship between insulin resistance and oxidative stress in vivo].
OBJECTIVE
The relationship between oxidative stress in vivo and insulin resistance was examined.


METHODS
This study included 87 patients, 46 males and 41 females (mean age 63 +/- 10 years), without coronary artery disease. The homeostasis assessment insulin resistance (HOMA-IR) (fasting blood sugar x fasting immunoreactive insulin/405), a marker for insulin resistance, was measured. The patients were divided into three groups: the noninsulin resistance group (N-IR group) without diabetes mellitus (DM) and with fasting blood glucose level of 126 mg/dl and HOMA-IR < or = 1.73 (n = 44), the insulin resistance group (IR group) without diabetes mellitus and with fasting blood glucose level of 126 mg/dl and HOMA-IR > 1.73 (n = 29), and the DM group (type 2 diabetes mellitus) (n = 14). Urinary 8-iso-prostaglandin F2 alpha (U-8-iso-PGF2 alpha) excretion was measured as a marker of in vivo oxidative stress.


RESULTS
There were significantly more obese patients in the IR group than in the N-IR group (62% vs 25%, p = 0.001), and the remnant-like particle cholesterol level was significantly higher in the IR group than in the N-IR group (7.6 +/- 5.2 vs 4.6 +/- 1.5 mg/dl, p < 0.01). Patients in the IR group had a significantly larger number of coronary risk factors. U-8-iso-PGF2 alpha excretion was significantly higher in the IR group and DM groups (201 +/- 86, 191 +/- 136 vs 129 +/- 50 pg/mg. Cr, p < 0.0001, p = 0.01), and there was a significantly positive correlation between the number of coronary risk factors, fasting blood sugar and U-8-iso-PGF2 alpha concentration (correlation coefficient = 0.32, 0.37, p = 0.002, p = 0.0003). Multiple regression analysis showed that remnant-like particle cholesterol, fasting blood sugar and insulin resistance were independent factors for U-8-iso-PGF2 alpha concentration (p < 0.0001, p = 0.0007, p = 0.02).


CONCLUSIONS
Insulin resistance, remnant lipoprotein and hyperglyceridemia are deeply involved in oxidative stress in vivo.
Hitsumoto
Takashi
T
Department of Cardiovascular Center, Sakura Hospital, Toho University School of Medicine, Shimoshizu 564-1, Sakura, Chiba 285-0841.
Iizuka
Takuo
T
Takahashi
Mao
M
Yoshinaga
Kunio
K
Matsumoto
Jun
J
Shimizu
Kazuhiro
K
Kaku
Michihisa
M
Sugiyama
Yuko
Y
Sakurai
Takeshi
T
Aoyagi
Kaneyuki
K
Kanai
Masahito
M
Noike
Hirofumi
H
Ohsawa
Hidefumi
H
Watanabe
Hitoshi
H
Shirai
Kohji
K
D001786:Blood Glucose / Q000032:analysis; D002784:Cholesterol / Q000097:blood; D003920:Diabetes Mellitus / Q000097:blood; D015237:Dinoprost / Q000031:analogs & derivatives*; D028441:F2-Isoprostanes / Q000652:urine; D005260:Female; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008074:Lipoproteins / Q000097:blood; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress / Q000502:physiology*; D012044:Regression Analysis
D001786:Blood Glucose; D028441:F2-Isoprostanes; D008074:Lipoproteins; C075750:8-epi-prostaglandin F2alpha; D002784:Cholesterol; D015237:Dinoprost