l-Anserine, an imidazole peptide, has a variety
of physiological
activities, but its effects on skeletal muscle differentiation and
muscle contractile force remain unknown. Thus, in this study, we investigated
the effect of l-anserine on muscle differentiation and muscle
contractile force in human skeletal muscle cells. In two-dimensional
culture, 1 μM l-anserine significantly increased the
myotube diameters (26.5 ± 1.71, 27.7 ± 1.08, and 28.8 ±
0.85 μm with 0, 0.1, and 1 μM l-anserine, respectively)
and the expression levels of genes involved in muscle differentiation
and the sarcomere structure. In three-dimensional culture, 1 μM l-anserine significantly increased the contractile force of
engineered human skeletal muscle tissues cultured on a microdevice
(1.99 ± 0.30, 2.17 ± 0.62, 2.66 ± 0.39, and 3.28 ±
0.85 μN with 0, 0.1, 0.5, and 1 μM l-anserine,
respectively). l-Anserine also increased the myotube diameters
and the proportion of myotubes with sarcomere structures in the cultured
tissues. Furthermore, the histamine receptor 1 (H1R) antagonist attenuated
the l-anserine-induced increase in the contractile force,
suggesting the involvement of H1R in the mechanism of action of l-anserine. This study showed for the first time that l-anserine enhances muscle differentiation and muscle contractility
via H1R.