The purpose of this study is to learn about how the antioxidant, lipoic acid, works in the body and how it may help in the management of relapsing remitting and secondary progressive multiple sclerosis. This study will compare how subject's and healthy volunteers bodies absorb and break down the supplement. This information may help in developing new therapies.

Subjects (healthy control, relapsing remitting MS and secondary progressive MS) will be recruited through patients of investigators at Portland VA Medical Center (PVAMC), Oregon Health & Science University (OHSU), and the community using flyers and word of mouth.

The following will occur during screening:

• Medical History Questionnaire to include questions about drug and alcohol use
• Self Administered Expanded Disability Status Scale (EDSS) Questionnaire (MS participants only)
• Vital Signs (heart rate, respiratory rate, blood pressure) will be measured and recorded
• Physical Exam (MS participants only unless necessary, based on the Medical History Questionnaire or vital signs, to ensure participant safety)
• Neurological Exam (MS participants only unless necessary, based on the Medical History Questionnaire or vital signs, to ensure participant safety)
• Weight
• Urine pregnancy test, if applicable
• Anemia testing by finger stick (approximately 1 drop)

The rest of the study involves

• Blood draws before lipoic acid is given, 1 hour, 2 hours, 3 hours, 4 hours, 24 and 48 hours after LA is given (3 ½ tablespoons)
• Subjects will receive breakfast before they take LA
• Subjects will take 4 - 300 mg capsules of lipoic acid (LA) for a total of 1200mg with about 1 cup of water

Blood will be processed to obtain plasma (from which lipoic acid concentrations will be measured) and PBMCs (from which cAMP and cytokines/chemokines will be measured).

Inclusion/Exclusion criteria for MS subjects.

Inclusion criteria:

1. Adult at least 18 years of age able to provide informed consent
2. Currently diagnosed with relapsing remitting or secondary progressive MS

Exclusion criteria:

1. Self-reported current substance/alcohol abuse/dependence or sobriety for less than 90 days
2. History of traumatic brain injury as defined by a loss of consciousness of greater than 30 minutes
3. History of a medical condition associated with persisting cognitive problems or serious central nervous system dysfunction (e.g., brain tumor,dementia)
4. MS exacerbation within 30 days of study entry
5. Systemically administered corticosteroids within 30 days of study entry
6. Pregnant or breast-feeding
7. Anti-coagulant use such as Heparin, Coumadin, or Aspirin while enrolled in the study
8. Other significant health problem (e.g. active coronary heart disease, liver disease, pulmonary disease, diabetes mellitus) that might increase the risk of subject experiencing adverse events
9. Any condition which would make the subject, in the opinion of the investigator, unsuitable for the study
10. Anemia as indicated by a POC hemoglobin <12
11. Subjects of child bearing potential or subjects capable of causing pregnancy who are sexually active and unwilling to use effective contraceptive methods for the duration of the study

Inclusion/ Exclusion criteria for healthy controls.

Inclusion criteria:

1) Adult at least 18 years of age able to provide informed consent

Exclusion criteria:

1. Self-reported current substance/alcohol abuse/dependence or sobriety for less than 90 days
2. History of traumatic brain injury as defined by a loss of consciousness of greater than 30 minutes
3. History of a medical condition associated with persisting cognitive problems or serious central nervous system dysfunction (e.g., brain tumor,dementia)
4. Pregnant or breast-feeding
5. Anti-coagulant use such as Heparin, Coumadin, or Aspirin while enrolled in the study
6. Other significant health problem (e.g. active coronary heart disease, liver disease, pulmonary disease, diabetes mellitus) that might increase the risk of subject experiencing adverse events
7. Any condition which would make the subject, in the opinion of the investigator, unsuitable for the study
8. Anemia as indicated by a POC hemoglobin <12
9. Subjects of child bearing potential or subjects capable of causing pregnancy who are sexually active and unwilling to use effective contraceptive methods for the duration of the study