| Project/Area Number |
16390256
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Neurology
|
|---|
| Research Institution | Teikyo University |
|---|
Principal Investigator |
SHIMIZU Teruo Teikyo University, School of Medicine, Professor (00107666)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MATSUMURA Kiichiro Teikyo University, School of Medicine, Associate Professor (50260922)
SAITO Fumiaki Teikyo University, School of Medicine, Assistant Professor (40286993)
新井 謙 帝京大学, 医学部, 助手 (00349250)
|
|---|
| Project Period (FY) |
2004 – 2007
|
| Project Status |
Completed (Fiscal Year 2007)
|
| Budget Amount *help |
¥15,250,000 (Direct Cost: ¥14,200,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2007: ¥4,550,000 (Direct Cost: ¥3,500,000、Indirect Cost: ¥1,050,000)
Fiscal Year 2006: ¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2005: ¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2004: ¥3,700,000 (Direct Cost: ¥3,700,000)
|
|---|
| Keywords | α-dystroglycan / α-dystroglycanopathy / laminin / protein convertase / Large / fukutin / congenital muscular dystrophy / α dystroglycanopathy / 福山型先天性筋ジストロフィー / dystroglycan / matrix metalloproteinase / extracellular matrix / 筋ジストロフィー鶏 / 遠位型ミオパチー |
|---|
| Research Abstract |
Dystroglycan (DG) links the extracellular matrix with cytoskeleton. Recently, mutations of the genes encoding putative glycosyltransferases were identified in several congenital muscular dystrophies and aberrant glycosylation of α-DG has been implicated in their pathogeneses (α-dystroglycanopathy). In this study, we have obtained several novel findings concerning the molecular pathogenesis of a-dystroglycanopathy.
(1) We found the protease activity that degrades the extracellular domain of β-DG specifically. This activity was suppressed by the inhibitor of MMP-2 and MMP-9. Cultured cells secreted MMP-2 and MMP-9 into the culture medium. Active MMP-2 and MMP-9 enzymes degraded the β-DG. MMP-2 and MMP-9 were activated in Duchenne muscular dystrophy and sarcoglycanopathyas well as in their model animals. These results indicate that inhibitors of MMP-2 and MMP-9 may be effective for these diseases.
(2) Peripheral nerve myelination was defective in the fukutin-deficient chimeric mice, a mouse
… More
model of Fukuyama-type congenital muscular dystrophy. The density of myelinated nerve fibers was significantly decreased and clusters of abnormally large non-myelinated axons were ensheathed by a single Schwann cell. The sugar chain moiety and laminin-binding activity of α-DG were severely reduced in the peripheral nerve of the chimeric mice. The clustering of acetylcholine receptor was defective and neuromuscular junctions are fragmented in appearance in these mice. These results demonstrate that dysmyelination of peripheral nerve should be carefully watched in congenital muscular dystrophies.
(3) We found the cleavage and secretion of the N-terminal domain of α-DG (α-DG-N). Secreted α-DG-N was both N- and 0-glycosylated.α-DG-N was detectable in the human serum and cerebrospinal fluid. These observations indicate that the cleavage of α-DG-N is a widespread event and suggest that the secreted α-DG-N might be transported via systemic circulation and that the level of α-DG-N may be altered in α-dystroglycanopathies. Less
|
