TY - JOUR
T1 - Adipose tissue interleukin-18 mRNA and plasma interleukin-18: effect of obesity and exercise
AU - Leick, Lotte
AU - Lindegaard, Birgitte
AU - Stensvold, Dorthe
AU - Plomgaard, Peter
AU - Saltin, Bengt
AU - Pilegaard, Henriette
N1 - Keywords: Adipose Tissue; Adult; Body Mass Index; Exercise; Female; Humans; Insulin Resistance; Interleukin-18; Male; Obesity; RNA, Messenger
PY - 2007
Y1 - 2007
N2 - OBJECTIVES: Obesity and a physically inactive lifestyle are associated with increased risk of developing insulin resistance. The hypothesis that obesity is associated with increased adipose tissue (AT) interleukin (IL)-18 mRNA expression and that AT IL-18 mRNA expression is related to insulin resistance was tested. Furthermore, we speculated that acute exercise and exercise training would regulate AT IL-18 mRNA expression. RESEARCH METHODS AND PROCEDURES: Non-obese subjects with BMI < 30 kg/m(2) (women: n = 18; men; n = 11) and obese subjects with BMI >30 kg/m(2) (women: n = 6; men: n = 7) participated in the study. Blood samples and abdominal subcutaneous AT biopsies were obtained at rest, immediately after an acute exercise bout, and at 2 hours or 10 hours of recovery. After 8 weeks of exercise training of the obese group, sampling was repeated 48 hours after the last training session. RESULTS: AT IL-18 mRNA content and plasma IL-18 concentration were higher (p < 0.05) in the obese group than in the non-obese group. AT IL-18 mRNA content and plasma IL-18 concentration was positively correlated (p < 0.05) with insulin resistance. While acute exercise did not affect IL-18 mRNA expression at the studied time-points, exercise training reduced AT IL-18 mRNA content by 20% in both sexes. DISCUSSION: Because obesity and insulin resistance were associated with elevated AT IL-18 mRNA and plasma IL-18 levels, the training-induced lowering of AT IL-18 mRNA content may contribute to the beneficial effects of regular physical activity with improved insulin sensitivity.
AB - OBJECTIVES: Obesity and a physically inactive lifestyle are associated with increased risk of developing insulin resistance. The hypothesis that obesity is associated with increased adipose tissue (AT) interleukin (IL)-18 mRNA expression and that AT IL-18 mRNA expression is related to insulin resistance was tested. Furthermore, we speculated that acute exercise and exercise training would regulate AT IL-18 mRNA expression. RESEARCH METHODS AND PROCEDURES: Non-obese subjects with BMI < 30 kg/m(2) (women: n = 18; men; n = 11) and obese subjects with BMI >30 kg/m(2) (women: n = 6; men: n = 7) participated in the study. Blood samples and abdominal subcutaneous AT biopsies were obtained at rest, immediately after an acute exercise bout, and at 2 hours or 10 hours of recovery. After 8 weeks of exercise training of the obese group, sampling was repeated 48 hours after the last training session. RESULTS: AT IL-18 mRNA content and plasma IL-18 concentration were higher (p < 0.05) in the obese group than in the non-obese group. AT IL-18 mRNA content and plasma IL-18 concentration was positively correlated (p < 0.05) with insulin resistance. While acute exercise did not affect IL-18 mRNA expression at the studied time-points, exercise training reduced AT IL-18 mRNA content by 20% in both sexes. DISCUSSION: Because obesity and insulin resistance were associated with elevated AT IL-18 mRNA and plasma IL-18 levels, the training-induced lowering of AT IL-18 mRNA content may contribute to the beneficial effects of regular physical activity with improved insulin sensitivity.
U2 - 10.1038/oby.2007.528
DO - 10.1038/oby.2007.528
M3 - Journal article
C2 - 17299108
SN - 1930-7381
VL - 15
SP - 356
EP - 363
JO - Obesity
JF - Obesity
IS - 2
ER -
