Becker's Muscular Dystrophy, Duchenne Muscular Dystrophy, Dystrophinopathy
Conditions
Keywords
L-arginine supplement study
Brief summary
The purpose of the study is to assess the safety, tolerability, and effects of L-Arginine on muscles in boys with dystrophinopathy on corticosteroids. Specifically, to see if L-arginine reduces muscle signal abnormalities on MRI done pre and post 30 days of L-arginine administration.
Detailed description
Dystrophinopathy is a muscular dystrophy (includes Duchenne or Becker's Muscular Dystrophy) that can be a lethal muscle disorder resulting from defects in the gene for dystrophin, a structural protein required to maintain muscle integrity. Absence of functional dystrophin leaves the muscle membrane vulnerable to damage during contraction. This damage can be exacerbated by an inflammatory response leading to myofiber necrosis. L-arginine is a widely available dietary supplement amino acid postulated to affect dystrophinopathy in several favorable ways: upregulation of utrophin, vasodilation in muscle via nitric oxide, enhanced synthesis of creatine, increase levels of growth hormone. We hypothesize that administration of L-arginine may increase levels of creatine and growth hormone and in turn reduce the extent of myofiber damage in our patients with dystrophinopathy
Interventions
DRUGL-arginine
Subjects will receive oral L-Arginine (0.3 grams/kg/day, divided 2 times per day, not to exceed 14 grams/day)
Sponsors
Massachusetts General Hospital
Study design
Allocation
NON_RANDOMIZED
Intervention model
SINGLE_GROUP
Masking
NONE
Eligibility
Sex/Gender
MALE
Age
7 Years to 11 Years
Healthy volunteers
No
Inclusion criteria
* Confirmation of diagnosis of dystrophinopathy, documented by clinical exam and dystrophin DNA mutation analysis * Ambulatory male subjects between the ages of 7-11 years * Stable dosage of corticosteroids for 3 months prior to entry (Screening/Baseline Day 0) and during treatment period * Able to follow instructions and give assent * Able to complete nonsedated MR
Exclusion criteria
* Presence of metallic orthopedic hardware in the lower extremity that could affect MRI/MRS measurements * Routine MRI
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| MRI/MRS of calf muscle | Day 0 and Day 30 | MRI/MRS will be performed of the calf muscle in all subjects (N=8) to assess muscle signal abnormalities on MRI and creatine levels on MRS, done at the start of the study (Day 0) and at the end of the study (Day 30), after 30 days of L-arginine administration. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Blood tests | Day 0 and Day 30 | We will obtain safety labs \[complete blood count (CBC) and comprehensive metabolic panel (CMP)\] from all subjects (N =8), at day 0 and day 30, after 30 days of oral L-argninine administration. |
| Assessment of muscle strength and function | Day 0 and Day 30 | Measurements of upper and lower extremity strength will be performed using a hand-held dynamometer. Functional tests will also be performed which include time to walk specified distances and time to climb stairs. |
| Pulmonary function tests | Day 0 and Day 30 | Subjects will have pulmonary function studies to assess forced vital capacity |
Countries
United States
Outcome results
None listed