Fig 1. Alteration of total protein contents in cultured human skeletal muscle cells: Winter-hibernation period vs. summer-active period.

(A) Typical immunostaining images of cultured human skeletal muscle cells at 5 days of differentiation following 24 h treatment with bear serum. Red, myosin heavy chain (MF20); blue, DAPI. The occasional small bright red dot is a staining artifact. The scale bar shows 100 μm. (B) The number of DAPI-positive signals per field was counted as the nuclei number. (C) The total protein contents were significantly increased in cultured myotubes following 24 h treatment with hibernating bear serum compared to the active period serum. Data are expressed as mean ± standard errors. Significant differences: #, p < 0.05.