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Nitric Oxide Production in MELAS Syndrome

This study has been completed.
Information provided by (Responsible Party):
Fernando Scaglia, Baylor College of Medicine Identifier:
First received: April 19, 2011
Last updated: April 1, 2016
Last verified: April 2016


Baylor College of Medicine and Texas Children's Hospital are recruiting individuals with MELAS syndrome for a clinical study. MELAS syndrome is a mitochondrial disease; patients with this disease have muscle weakness and often develop brain strokes, where blood does not flow normally to different parts of the brain. It is believed that these strokes could be due to decreased production of nitric oxide, a naturally occurring compound important for normal blood vessel function. Nitric oxide is made from arginine and citrulline that are normally found in our bodies.

What is the purpose of this study? The purpose of this study is to measure nitric oxide in individuals with MELAS and see if giving arginine or citrulline will increase the formation of nitric oxide. Nitric oxide is thought to be helpful in preventing strokes. Therefore, if arginine and/or citrulline are shown to increase the formation of nitric oxide, they could be used to prevent or treat the strokes in patients with MELAS syndrome.

Condition Intervention Phase
MELAS Syndrome
Dietary Supplement: Arginine and citrulline supplementations
Early Phase 1

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Arginine Flux and Nitric Oxide Production in Patients With MELAS Syndrome and the Effect of Arginine and Citrulline Supplementation

Resource links provided by NLM:

Further study details as provided by Baylor College of Medicine:

Primary Outcome Measures:
  • Change in nitric oxide production [ Time Frame: Nitric oxide production will be measured at baseline before supplementation and after 48 hours of arginine or citrulline supplementation ]

Enrollment: 30
Study Start Date: July 2009
Study Completion Date: April 2016
Primary Completion Date: April 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: arginine supplementation
Oral L-arginine supplementation will be administered to subjects with MELAS for 48 hours at a dose of 10 grams per M2 per day. Arginine will be given every 4 hours.
Dietary Supplement: Arginine and citrulline supplementations
Arginine or citrulline will be given orally at dose of 10 grams per meter square body surface area per day divided every 4 hours.
Active Comparator: citrulline supplementation
Oral L-citrulline supplementation will be administered to subjects with MELAS for 48 hours at a dose of 10 grams per M2 per day. Citrulline will be given every 4 hours
Dietary Supplement: Arginine and citrulline supplementations
Arginine or citrulline will be given orally at dose of 10 grams per meter square body surface area per day divided every 4 hours.

Detailed Description:

What does the study involve? Individuals with MELAS syndrome will be admitted twice to the General Clinical Research Center (GCRC) at Texas Children's Hospital. Each time they will stay for five days, during which a special diet will be provided. Nitric oxide production will be measured by stable isotopes infusion technique that involves placing small tubes in veins (IV catheter), blood sampling, and injecting a harmless stable isotope. Stable isotopes are forms of normal compounds that can be measured accurately. They are not radioactive and there are no known risks to giving them; they are already part of your body in small amounts.

During the first admission nitric oxide levels will be measured, then arginine supplementation will be provided for 48 hours, after which nitric oxide levels will be re-measured to determine the effect of arginine supplementation. During the second admission, the effect of citrulline supplementation will be measured.

Who can participate in the study? Adults or children affected with MELAS syndrome and carrying the DNA change that causes the condition (3243 A>G mutation) can participate. Adults without MELAS disease will be recruited to participate as control subjects.

How to get more information? Subjects interested in participation or getting more information can contact Dr. Ayman El-Hattab at email:, office phone: 832-822-4289, cell phone: 646-660-5666, or pager: 832-824-7243 (5523).


Ages Eligible for Study:   3 Years to 65 Years   (Child, Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  1. Age from 3 - 65 years
  2. Clinical diagnosis of MELAS syndrome
  3. Carrying the m.3243A>G mutation

Exclusion Criteria:

  1. Having acute or chronic disease or physical disability that will interfere with the ability to undergo the study procedures
  2. Being pregnant
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT01339494

United States, Texas
Texas Children's Hospital
Houston, Texas, United States, 77030
Sponsors and Collaborators
Baylor College of Medicine
Principal Investigator: Fernando Scaglia, M.D. Baylor College of Medicine
  More Information

Responsible Party: Fernando Scaglia, Professor, Baylor College of Medicine Identifier: NCT01339494     History of Changes
Other Study ID Numbers: H-24783
Study First Received: April 19, 2011
Last Updated: April 1, 2016
Individual Participant Data  
Plan to Share IPD: Yes
Plan Description: Yes the data have been made available to

Additional relevant MeSH terms:
Mitochondrial Encephalomyopathies
Mitochondrial Myopathies
Muscular Diseases
Mitochondrial Diseases
MELAS Syndrome
Pathologic Processes
Musculoskeletal Diseases
Brain Diseases, Metabolic, Inborn
Brain Diseases, Metabolic
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Cerebral Small Vessel Diseases
Cerebrovascular Disorders
Neuromuscular Diseases
Vascular Diseases
Cardiovascular Diseases
Metabolism, Inborn Errors
Genetic Diseases, Inborn
Metabolic Diseases
Nitric Oxide
Bronchodilator Agents
Autonomic Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Anti-Asthmatic Agents
Respiratory System Agents
Free Radical Scavengers processed this record on May 25, 2017