Increased skeletal muscle expression of the endoplasmic reticulum chaperone GRP78 in patients with myasthenia gravis

J Neuroimmunol. 2014 Aug 15;273(1-2):72-6. doi: 10.1016/j.jneuroim.2014.05.006. Epub 2014 May 21.


In myasthenia gravis (MG), damage to neuromuscular junctions may induce endoplasmic reticulum (ER) stress in skeletal muscles. In the current study, skeletal muscles obtained from patients with MG exhibited upregulation of glucose-regulated protein 78 (GRP78) mRNA that was activated by ER stress. Furthermore, GRP78 mRNA expression was higher in patients with MG and myositis than in patients with non-myopathy. We also observed a significant positive correlation between GRP78 mRNA expression and GRP78 protein levels and between GRP78 mRNA expression and age of MG onset. Our findings suggest that muscle weakness in MG might be caused by both neuromuscular junction disruption and ER stress.

Keywords: Endoplasmic reticulum (ER) stress response; Glucose-regulated protein 78 (GRP78); Myasthenia gravis; Skeletal muscle.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Aged
  • Endoplasmic Reticulum Chaperone BiP
  • Female
  • Heat-Shock Proteins / genetics
  • Heat-Shock Proteins / metabolism*
  • Humans
  • Male
  • Middle Aged
  • Muscle, Skeletal / metabolism*
  • Myasthenia Gravis / complications
  • Myasthenia Gravis / pathology*
  • RNA, Messenger / metabolism
  • Statistics, Nonparametric
  • Thymoma / etiology
  • Thymoma / metabolism
  • Thymoma / pathology
  • Up-Regulation / physiology*
  • Young Adult


  • Endoplasmic Reticulum Chaperone BiP
  • HSPA5 protein, human
  • Heat-Shock Proteins
  • RNA, Messenger