Arginine promotes myogenic differentiation and myotube formation through the elevation of cytoplasmic calcium concentration

Abstract

This study aimed to explore the mechanism underlying arginine-promoted myogenesis of myoblasts. C2C12 cells were cultured with a medium containing 0.1, 0.4, 0.8, or 1.2 mmol/L arginine, respectively. Cell proliferation, viability, differentiation indexes, cytoplasmic Ca 2+ concentration, and relative mRNA expression levels of myogenic regulatory factors (MRF) and key Ca 2+ channels were measured in the absence or presence of 2 chemical inhibitors, dantrolene (DAN, 10 μmol/L) and nisoldipine (NIS, 10 μmol/L), respectively. Results demonstrated that arginine promoted myogenic differentiation and myotube formation. Compared with the control (0.4 mmol/L arginine), 1.2 mmol/L arginine upregulated the relative mRNA expression levels of myogenin ( MyoG) and Myomaker at d 2 during myogenic induction ( P < 0.05). Cytoplasmic Ca 2+ concentrations were significantly elevated by arginine supplementation at d 2 and 4 ( P < 0.05). Relative mRNA expression levels of Ca 2+ channels including the type 1 ryanodine receptor (RyR1) and voltage-gated Ca 2+ channel ( Cav1.1) were upregulated by 1.2 mmol/L arginine during 2-d myogenic induction ( P < 0.01). However, arginine-promoted myogenic potential of myoblasts was remarkably compromised by DAN and NIS, respectively ( P < 0.05). These findings evidenced that the supplementation of arginine promoted myogenic differentiation and myotube formation through increasing cytoplasmic Ca 2+ concentration from both extracellular and sarcoplasmic reticulum Ca 2+ .

l-Arginine Alleviates LPS-Induced Oxidative Stress and Apoptosis via Activating SIRT1-AKT-Nrf2 and SIRT1-FOXO3a Signaling Pathways in C2C12 Myotube Cells

“…Previous studies showed that l -Arg could induced C2C12 myoblasts differentiation. Therefore, in this study, we used differentiated C2C12 cells [ 34 , 35 ]. The different concentrations of l -Arg were used to treat LPS-induced C2C12 myotube cells, to explore the mechanism of l -Arg alleviating oxidative stress and apoptosis, and to provide a new idea for alleviating muscle injury.…”

Virus-Induced Membrane Fusion in Neurodegenerative Disorders

“…Under normal circumstances, arginine functions as a physiological fusogen that facilitates the merger of myoblasts as well as the fusion of intra and extracellular vesicles in the CNS ( Das et al., 2004 ; Koike and Jahn, 2019 ; Gong et al., 2021 ). The positively charged guanidinium side chains, a unique characteristic of this amino acid, pierce cell membranes, forming pores that may facilitate both viral uptake and pTau egress ( Walrant et al., 2017 ; Nyenhuis et al., 2021 ).…”

Arginine Regulates Skeletal Muscle Fiber Type Formation via mTOR Signaling Pathway

“…The concentration of 0.4 mM arginine in the control group was the concentration of arginine contained in the growth medium (high-glucose DMEM medium) without additional arginine. The concentrations of 1.2 mM and 3.6 mM arginine in the treatment group were in reference to the dosages of arginine treated with the C2C12 cell line in other studies [ 16 , 24 , 25 ]. Consistent with cell morphology ( Figure 5 A), Arg significantly promoted the mRNA expression of myomarker ( Figure 5 D), suggesting Arg can promote myoblast myotube fusion.…”

“…When the cells reached 90% confluency, DMEM with 2% horse serum (HyClone, Logan, UT, USA) was added for 6 days to induce myoblast differentiation into myotubes. On day 1 of differentiation, treating C2C12 with 1.2 mM or 3.6 mM of arginine for 72 h. The dosage of arginine was in reference to other studies [ 16 , 24 , 25 ]. On days 0, 2, and 4 of differentiation, DMSO or 1 μM of rapamycin (Beyotime, Shanghai, China) was added to the complete medium to culture the cells.…”