TY - JOUR
T1 - Exercise normalises overexpression of TNF-alpha in knockout mice
AU - Keller, Charlotte
AU - Keller, Pernille
AU - Giralt, Mercé
AU - Hidalgo, Juan
AU - Pedersen, Bente Klarlund
PY - 2004/8/13
Y1 - 2004/8/13
N2 - TNF-alpha is linked with insulin resistance, as greater amounts of TNF are detected in muscle and adipose tissue in glycemically challenged people and TNF-alpha inhibits insulin receptor signalling. However, what modulates this overexpression of TNF-alpha is currently unknown. We examined the effect of 1 h exercise on overexpression of the TNF-alpha gene in TNF receptor 1 and 2 knockout mice. IL-6 knockout mice were included to elucidate the importance of IL-6 in regulating TNF-alpha in response to exercise. TNF-alpha gene expression was over-expressed in muscle in both TNFR knockout models. TNF-alpha overexpression returned to normal levels after exercise in the TNF-alpha receptor knockout models. In IL-6 knockout mice, a modest decrease in TNF-alpha was also observed. These data suggest that TNF-alpha-induced insulin resistance can be regulated by a single exercise bout by normalising TNF-alpha expression. This exercise effect can be mediated via IL-6, but also an IL-6 independent mechanism seems to exist.
AB - TNF-alpha is linked with insulin resistance, as greater amounts of TNF are detected in muscle and adipose tissue in glycemically challenged people and TNF-alpha inhibits insulin receptor signalling. However, what modulates this overexpression of TNF-alpha is currently unknown. We examined the effect of 1 h exercise on overexpression of the TNF-alpha gene in TNF receptor 1 and 2 knockout mice. IL-6 knockout mice were included to elucidate the importance of IL-6 in regulating TNF-alpha in response to exercise. TNF-alpha gene expression was over-expressed in muscle in both TNFR knockout models. TNF-alpha overexpression returned to normal levels after exercise in the TNF-alpha receptor knockout models. In IL-6 knockout mice, a modest decrease in TNF-alpha was also observed. These data suggest that TNF-alpha-induced insulin resistance can be regulated by a single exercise bout by normalising TNF-alpha expression. This exercise effect can be mediated via IL-6, but also an IL-6 independent mechanism seems to exist.
KW - Adipose Tissue/physiology
KW - Animals
KW - Antigens, CD/genetics
KW - Female
KW - Insulin Resistance/genetics
KW - Interleukin-6/deficiency
KW - Male
KW - Mice
KW - Mice, Knockout
KW - Muscle, Skeletal/physiology
KW - Physical Conditioning, Animal/physiology
KW - RNA, Messenger/genetics
KW - Receptors, Tumor Necrosis Factor/deficiency
KW - Receptors, Tumor Necrosis Factor, Type I
KW - Receptors, Tumor Necrosis Factor, Type II
KW - Tumor Necrosis Factor-alpha/genetics
U2 - 10.1016/j.bbrc.2004.06.129
DO - 10.1016/j.bbrc.2004.06.129
M3 - Journal article
C2 - 15358232
SN - 0006-291X
VL - 321
SP - 179
EP - 182
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 1
ER -