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Updated: Jan 27, 2026

Stable Knockdown of Genes Encoding Extracellular Matrix Proteins in the C2C12 Myoblast Cell Line Using Small-Hairpin shRNA
Published on: February 12, 2020
AMPK/FOXO1 signaling pathway is indispensable in visfatin-regulated myosin heavy chain expression in C2C12 myotubes
Li Na Zhou1, Ying Ni Lin2, Chen Juan Gu2
1Department of Respiratory and Critical Care Medicine, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China; Department of Respiratory Medicine, Ruijin Hospital North, Shanghai Jiao Tong University School of Medicine, Shanghai 281000, China.
Objective:
Few studies have addressed the effects of visfatin on skeletal muscle remodeling. The aim of the study was to investigate the effects of visfatin on the expressions of myosin heavy chain (MHC) and its isoforms, the major indicator of fiber types and contractile properties of skeletal muscle.
Materials And Methods:
Levels of MHC, MHC I, MHC IIa, MHC IIb, adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK), p-AMPK and forkhead box protein O1 (FOXO1) were tested in visfatin-treated C2C12 myotubes. C2C12 myotubes were treated with visfatin combined with AMPK inhibitor or AMPK activator to investigate the role of AMPK in visfatin-mediated MHC expression. FOXO1 was overexpressed or knocked down in C2C12 myotubes to explore the role of FOXO1 in visfatin-mediated MHC expression.
Results:
Compared with the vehicle group, treatment with 5 μg/ml visfatin increased the levels of total MHC and its isoforms, MHC I, MHC IIa and MHC IIb, by 1.93, 1.84, 1.80, and 1.92 folds, respectively (all p = 0,001). Visfatin suppressed AMPK phosphorylation and decreased FOXO1 expression in C2C12 myotubes. The effects of visfatin on MHC I and MHC IIa expression were canceled by AMPK activator AICAR. FOXO1 overexpression minimized the visfatin-induced upregulation of MHC I, MHC IIa and MHC IIb. The effect of AMPK activator AICAR on MHC and its isoforms expression was minimized by knockdown of FOXO1.
Conclusions:
The findings revealed that visfatin promoted expressions of MHC and its isoforms in C2C12 myotubes via suppressing AMPK/FOXO1 signaling pathway.
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