TY - JOUR
T1 - Epinephrine stimulates IL-6 expression in skeletal muscle and C 2C12 myoblasts
T2 - Role of c-Jun NH2-terminal kinase and histone deacetylase activity
AU - Frost, Robert A.
AU - Nystrom, Gerald J.
AU - Lang, Charles H.
PY - 2004/5
Y1 - 2004/5
N2 - Although an individual's genetic makeup is a major determinant of muscle mass, other influences, such as hormones, cytokines, nutrition, and exercise can also modulate muscle size. IL-6 is an important inflammatory cytokine. Mice that overexpress IL-6 fail to thrive and/or have reduced skeletal muscle mass. The purpose of the present study was to determine whether the stress hormone epinephrine increases inflammatory cytokine expression in skeletal muscle and muscle cells. Infusion of epinephrine in vivo for 2 h increased IL-6 protein (15-fold) and mRNA (40-fold) in skeletal muscle but not in liver. Epinephrine had a similar effect in C2C12 muscle cells, where the hormone increased IL-6 protein and mRNA in a dose- and time-dependent manner. Epinephrine-stimulated IL-6 expression was attenuated by the α-adrenergic receptor antagonist phentolamine and completely blocked by either the β1/2-adrenergic receptor antagonist propranalol or the β2-antagonist ICI-118551. The transcriptional inhibitor DRB and the synthetic glucocorticoid dexamethasone also blocked epinephrine-induced IL-6. SP-600125 (a JNK inhibitor) and SB-202190 (a p38 MAP kinase inhibitor) completely blocked epinephrine-induced IL-6 synthesis. Endotoxin and epinephrine given together had a synergistic affect on IL-6 mRNA and protein expression. Trichostatin A (a histone deacetylase inhibitor) blocked both endotoxin- and epinephrine-induced IL-6 expression. These data suggest that epinephrine induces IL-6 synthesis in skeletal muscle in vivo and myocytes in vitro. Epinephrine utilizes predominantly the β1/2-adrenergic receptors to stimulate IL-6 synthesis. Endotoxin and epinephrine synergize to increase IL-6 mRNA expression. Optimal IL-6 synthesis may require both stress kinase and histone deacetylase activity.
AB - Although an individual's genetic makeup is a major determinant of muscle mass, other influences, such as hormones, cytokines, nutrition, and exercise can also modulate muscle size. IL-6 is an important inflammatory cytokine. Mice that overexpress IL-6 fail to thrive and/or have reduced skeletal muscle mass. The purpose of the present study was to determine whether the stress hormone epinephrine increases inflammatory cytokine expression in skeletal muscle and muscle cells. Infusion of epinephrine in vivo for 2 h increased IL-6 protein (15-fold) and mRNA (40-fold) in skeletal muscle but not in liver. Epinephrine had a similar effect in C2C12 muscle cells, where the hormone increased IL-6 protein and mRNA in a dose- and time-dependent manner. Epinephrine-stimulated IL-6 expression was attenuated by the α-adrenergic receptor antagonist phentolamine and completely blocked by either the β1/2-adrenergic receptor antagonist propranalol or the β2-antagonist ICI-118551. The transcriptional inhibitor DRB and the synthetic glucocorticoid dexamethasone also blocked epinephrine-induced IL-6. SP-600125 (a JNK inhibitor) and SB-202190 (a p38 MAP kinase inhibitor) completely blocked epinephrine-induced IL-6 synthesis. Endotoxin and epinephrine given together had a synergistic affect on IL-6 mRNA and protein expression. Trichostatin A (a histone deacetylase inhibitor) blocked both endotoxin- and epinephrine-induced IL-6 expression. These data suggest that epinephrine induces IL-6 synthesis in skeletal muscle in vivo and myocytes in vitro. Epinephrine utilizes predominantly the β1/2-adrenergic receptors to stimulate IL-6 synthesis. Endotoxin and epinephrine synergize to increase IL-6 mRNA expression. Optimal IL-6 synthesis may require both stress kinase and histone deacetylase activity.
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U2 - 10.1152/ajpendo.00560.2003
DO - 10.1152/ajpendo.00560.2003
M3 - Article
C2 - 14722032
AN - SCOPUS:1942518730
SN - 0193-1849
VL - 286
SP - E809-E817
JO - American Journal of Physiology - Endocrinology and Metabolism
JF - American Journal of Physiology - Endocrinology and Metabolism
IS - 5 49-5
ER -