RRC ID 52318
著者 Ono Y, Sakamoto K.
タイトル Lipopolysaccharide inhibits myogenic differentiation of C2C12 myoblasts through the Toll-like receptor 4-nuclear factor-κB signaling pathway and myoblast-derived tumor necrosis factor-α.
ジャーナル PLoS One
Abstract BACKGROUND:Circulating lipopolysaccharide (LPS) concentrations are often elevated in patients with sepsis or with various endogenous diseases that are associated with metabolic endotoxemia. Involuntary loss of skeletal muscle, termed muscle wasting, is commonly observed in these conditions, suggesting that circulating LPS might play an essential role in its development. Although impairment of muscle regeneration is an important determinant of skeletal muscle wasting, it is unclear whether LPS affects this process and, if so, by what mechanism. Here, we used the C2C12 myoblast cell line to investigate the effects of LPS on myogenesis.
METHODS:C2C12 myoblasts were grown to 80% confluence and induced to differentiate in the absence or presence of LPS (0.1 or 1 μg/mL); TAK-242 (1 μM), a specific inhibitor of Toll-like receptor 4 (TLR4) signaling; and a tumor necrosis factor (TNF)-α neutralizing antibody (5 μg/mL). Expression of a skeletal muscle differentiation marker (myosin heavy chain II), two essential myogenic regulatory factors (myogenin and MyoD), and a muscle negative regulatory factor (myostatin) was analyzed by western blotting. Nuclear factor-κB (NF-κB) DNA-binding activity was measured using an enzyme-linked immunosorbent assay.
RESULTS:LPS dose-dependently and significantly decreased the formation of multinucleated myotubes and the expression of myosin heavy chain II, myogenin, and MyoD, and increased NF-κB DNA-binding activity and myostatin expression. The inhibitory effect of LPS on myogenic differentiation was reversible, suggesting that it was not caused by nonspecific toxicity. Both TAK-242 and anti-TNF-α reduced the LPS-induced increase in NF-κB DNA-binding activity, downregulation of myogenic regulatory factors, and upregulation of myostatin, thereby partially rescuing the impairment of myogenesis.
CONCLUSIONS:Our data suggest that LPS inhibits myogenic differentiation via a TLR4-NF-κB-dependent pathway and an autocrine/paracrine TNF-α-induced pathway. These pathways may be involved in the development of muscle wasting caused by sepsis or metabolic endotoxemia.
巻・号 12(7)
ページ e0182040
公開日 2017-7-24
DOI 10.1371/journal.pone.0182040
PII PONE-D-17-03105
PMID 28742154
PMC PMC5524356
MeSH Animals Cell Differentiation Lipopolysaccharides / immunology* Mice Muscle Development* Myoblasts / cytology* Myoblasts / immunology Myoblasts / metabolism NF-kappa B / immunology* RNA, Messenger / genetics Signal Transduction* Toll-Like Receptor 2 / immunology Toll-Like Receptor 4 / genetics Toll-Like Receptor 4 / immunology* Tumor Necrosis Factor-alpha / immunology
IF 2.74
引用数 20
リソース情報
ヒト・動物細胞 C2C12(RCB0987)