Idiopathic inflammatory myopathies

Definition

The idiopathic inflammatory myopathies are a heterogeneous group of connective tissue diseases of unknown aetiology characterized by chronic inflammation of skeletal muscle, or myositis. The main types of idiopathic inflammatory myopathies are polymyositis, dermatomyositis and inclusion-body myositis.

Latest Research and Reviews

  • Reviews |

    In this Review the authors provide an account of prostaglandin and leukotriene involvement in muscle health and function. Various components of the arachidonic acid cascade are discussed in relation to their effect on the pathogenesis of inflammatory muscular diseases. Selective modulation of individual components of these pathways are considered as potential therapeutic options for the treatment of polymyositis and dermatomyositis.

    • Marina Korotkova
    •  & Ingrid E. Lundberg
  • Reviews |

    Although glucocorticoids are central to the treatment of idiopathic inflammatory myopathies, these drugs, paradoxically, have catabolic effects on skeletal muscle. Mechanisms that govern the beneficial and adverse effects of these agents are increasingly understood; as the authors explain, glucocorticoid therapy will be optimized as a result, but new targets that will lead to much-needed alternative therapeutic options are also expected to emerge.

    • Beatriz Y. Hanaoka
    • , Charlotte A. Peterson
    • , Craig Horbinski
    •  & Leslie J. Crofford
  • Research |

    Under certain conditions, endothelial cells can transform into mesenchymal cell types, a process known as endothelial-to-mesenchymal transition. Damian Medici et al. now provide evidence that this type of transition contributes to the generation of the ossified lesions of individuals with fibrodysplasia ossificans progressiva. Experiments in mice and in cultured endothelial cells indicate that activation of the ALK2 receptor in endothelial cells endows them with the ability to differentiate into a number of cell types.

    • Damian Medici
    • , Eileen M Shore
    • , Vitali Y Lounev
    • , Frederick S Kaplan
    • , Raghu Kalluri
    •  & Bjorn R Olsen
    Nature Medicine 16, 1400–1406
  • Reviews |

    Stratifying patients with myositis into clinically meaningful subtypes would be ideal for enabling research into pathogenic mechanisms and targeted therapies. Incomplete knowledge of the molecular pathways that underlie myositis, inappropriate classification criteria and a lack of specific agents have all been mutually hindering progress in treating these diseases, but, as the authors explain in this Review, insights into the mechanisms—immune and nonimmune—involved in myositis are precipitating wider progress in the field.

    • Mei Zong
    •  & Ingrid E. Lundberg

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