Endoplasmic Reticulum Stress Is Involved in Muscular Pathogenesis in Idiopathic Inflammatory Myopathies.

Objectives: Endoplasmic reticulum (ER) stress plays pivotal roles in the regulation of skeletal muscle damage and dysfunction in multiple disease conditions. We postulate the activation of ER stress in idiopathic inflammatory myopathies (IIM). Methods: Thirty-seven patients with immune-mediated necrotizing myopathy (IMNM), 21 patients with dermatomyositis (DM), 6 patients with anti-synthetase syndrome (ASS), and 10 controls were enrolled. The expression of ER stress-induced autophagy pathway was detected using histological sections, Western blot, and real-time quantitative Polymerase Chain Reaction. Results: ER stress-induced autophagy pathway was activated in biopsied muscle of patients with IMNM, DM, and ASS. The ER chaperone protein, glucose-regulated protein 78 (GRP78)/BiP expression in skeletal muscle correlated with autophagy, myofiber atrophy, myonecrosis, myoregeneration, and disease activity in IMNM. Conclusion: ER stress was involved in patients with IIM and correlates with disease activity in IMNM. ER stress response may be responsible for skeletal muscle damage and repair in IIM.

Hemorrhagic transformation after acute ischemic stroke caused by polycythemia vera: Report of two case.

BACKGROUND: Polycythemia vera (PV) is a chronic myeloproliferative disorder characterized by an increase in red blood cells in the peripheral blood. Previous work has reported the occurrence of thrombosis or hemorrhage arising in the cerebral vasculature secondary to PV. However, hemorrhagic transformation after PV-associated acute ischemic stroke has not been previously described. CASE SUMMARY: We herein present two cases of PV where hemorrhagic transformation occurred after an acute ischemic stroke. Case 1 was a 57-year-old woman with a history of hypertension who was admitted for left-sided weakness. Case 2 was a 68-year-old man who was admitted for a 10-d sudden left arm weakness. Imaging examinations for the two patients revealed hemorrhagic transformation after acute ischemic stroke. Both patients had JAK-2-V617F mutation and received antiplatelet therapy. Both of them had a good prognosis during the follow-up. CONCLUSION: This report suggested that hemorrhagic transformation may occur in acute ischemic stroke caused by PV. Antiplatelet drugs do not seem to influence the long-term outcomes in such patients. Future research should focus on establishing a standard antiplatelet treatment strategy for this condition.