Overview
The purpose of this study is to determine whether carnosine (a food ingredient found in chicken and red meat) supplementation (1 g) for 6 months in subjects with peripheral arterial disease (PAD); non-claudication or claudication) improves your walking ability. Previous studies with heart failure patients had shown that carnosine supplementation increases walking capacity in these patients.
Description
The objectives of this double-blinded longitudinal study are to determine whether carnosine supplementation (2 g) for 6 months in subjects with non-claudication and claudication peripheral arterial disease (PAD) improves walking ability. In this pilot study there will be enrolled 120 subjects that will be divided into placebo (n=60) and carnosine groups (n=60). The distance covered on the 6-minute walk test (6-MWT) and the pain free walking capacity on the treadmill before and after the placebo or carnosine supplementation will be measured. Ankle branchial index (ABI), blood flow by magnetic resonance imaging (MRI) and laser doppler flowmetry (LDF) before and after the carnosine and placebo supplementation will be also measured. In addition, the carnosine will be measured by 1HMRS, global metabolomics and proteomics in the skeletal muscle will be performed, a comprehensive lipid and metabolic panels of blood will be performed, uptake of carnosine in red blood cells (RBCs) will be measured, and carnosine aldehyde conjugates in the urine before and after 6 months of carnosine and placebo supplementation will be evaluated. Following completion of the study, the subjects will be followed up for another 3 months and examine the durability of carnosine supplementation.
Eligibility
Inclusion Criteria:
- Subjects between 40-80 years of age.
- English Speaking.
- ABI 0.4-<0.90.
- Willing to comply with protocol requirements.
- Able to provide informed consent.
Exclusion Criteria:
- Subjects with HIV, hepatitis, significant liver disease, active infection, anemia, organ transplant, renal disease requiring dialysis, lung disease requiring oxygen, significant congenital heart disease, cancer of any type, and untreated thyroid disease.
- Diagnosis of carnosinemia.
- Known allergy to L-carnosine or meat.
- Obesity from a known genetic defect.
- Critical limb ischemia with below or above the knee amputations or foot ulcers.
- Participating in other clinical trials.
- Presence of significant injury within 30 days before enrollment.
- Patients using dual antiplatelet therapies will be excluded for muscle biopsy.
- Poorly controlled diabetes (HbA1c >9% within 6 months)
- Subjects with a baseline 6MWT of less than 152.0 meter (498ft) or greater than 487.7 meters (1600ft)
- Subjects with internal metallic objects in body (cannot have MRI)