Cyclosporin A corrects mitochondrial dysfunction and muscle apoptosis in patients with collagen VI myopathies.

Abstract

Ullrich congenital muscular dystrophy and Bethlem myopathy are skeletal muscle diseases that are due to mutations in the genes encoding collagen VI, an extracellular matrix protein forming a microfibrillar network that is particularly prominent in the endomysium of skeletal muscle. Myoblasts from patients affected by Ullrich congenital muscular dystrophy display functional and ultrastructural mitochondrial alterations and increased apoptosis due to inappropriate opening of the permeability transition pore, a mitochondrial inner membrane channel. These alterations could be normalized by treatment with cyclosporin A, a widely used immunosuppressant that desensitizes the permeability transition pore independently of calcineurin inhibition. Here, we report the results of an open pilot trial with cyclosporin A in five patients with collagen VI myopathies. Before treatment, all patients displayed mitochondrial dysfunction and increased frequency of apoptosis, as determined in muscle biopsies. Both of these pathologic signs were largely normalized after 1 month of oral cyclosporin A administration, which also increased muscle regeneration. These findings demonstrate that collagen VI myopathies can be effectively treated with drugs acting on the pathogenic mechanism downstream of the genetic lesion, and they represent an important proof of principle for the potential therapy of genetic diseases.

• Authors: Luciano Merlini, Alessia Angelin, Tania Tiepolo, Paola Braghetta, Patrizia Sabatelli, Alessandra Zamparelli, Alessandra Ferlini, Nadir M Maraldi, Paolo Bonaldo, Paolo Bernardi
• Journal: Proceedings of the National Academy of Sciences of the United States of America (Proc Natl Acad Sci U S A) Vol. 105 Issue 13 Pg. 5225-9 (Apr 01 2008) ISSN: 1091-6490 [Electronic] United States
• PMID: 18362356 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Collagen Type VI
• Cyclosporine

Topics

• Adult
• Animals
• Apoptosis (drug effects)
• Biopsy
• Child
• Collagen Type VI (deficiency, genetics, metabolism)
• Cyclosporine (therapeutic use)
• Humans
• Mice
• Mice, Knockout
• Middle Aged
• Mitochondria (drug effects, metabolism)
• Muscular Diseases (drug therapy, genetics, metabolism, pathology)