Brown D R, Schmidt B, Groschup M H, Kretzschmar H A
Institut für Neuropathologie, Universität Göttingen, Germany.
Eur J Cell Biol. 1998 Jan;75(1):29-37. doi: 10.1016/S0171-9335(98)80043-5.
The prion protein (PrP) is a cell surface glycoprotein normally associated with neurones. Expression of the prion protein in cultured mouse myoblasts and myotubes suggests that the prion protein may play a physiological role in skeletal muscle. When myotubes differentiate from myoblasts prion protein expression is upregulated. Accompanying this increase is an upregulation of Cu/Zn superoxide dismutase (SOD-1) in myotubes. Muscle cells derived from mice deficient in cellular PrP (PrPc) show little increase in SOD-1 after differentiation from myoblasts to myotubes. Myoblasts and myotubes are resistant to the toxicity of a neurotoxic prion protein peptide (PrP106-126). However, in the presence of murine microglia, PrP106-126 causes a reduction in cell number. This effect is greater on myotubes than myoblasts. Even in the presence of microglia PrP106-126 is not toxic to muscle cells derived from PrP-deficient mice. Our results suggest that PrPc expression is associated with regulation of cellular resistance to oxidative stress in skeletal muscle.
朊病毒蛋白（PrP）是一种通常与神经元相关的细胞表面糖蛋白。朊病毒蛋白在培养的小鼠成肌细胞和肌管中的表达表明，朊病毒蛋白可能在骨骼肌中发挥生理作用。当成肌细胞分化为肌管时，朊病毒蛋白的表达会上调。伴随这种增加的是肌管中铜/锌超氧化物歧化酶（SOD-1）的上调。来自缺乏细胞朊病毒蛋白（PrPc）的小鼠的肌肉细胞在从成肌细胞分化为肌管后，SOD-1几乎没有增加。成肌细胞和肌管对神经毒性朊病毒蛋白肽（PrP106-126）的毒性具有抗性。然而，在存在小鼠小胶质细胞的情况下，PrP106-126会导致细胞数量减少。这种作用在肌管上比在成肌细胞上更明显。即使在存在小胶质细胞的情况下，PrP106-126对来自PrP缺陷小鼠的肌肉细胞也没有毒性。我们的结果表明，PrPc的表达与骨骼肌细胞对氧化应激的抗性调节有关。
