Oxalate Formation From Ascorbic Acid
University of Alabama at Birmingham
Summary
The purpose of this basic research study is to determine the contribution of endogenous ascorbic acid (AA) turnover to urinary oxalate excretion in both normal BMI and obese adult non-stone formers and calcium oxalate stone formers. The studies proposed will use diets of known nutrient composition, a stable isotope of ascorbic acid (13C6-AA) and mass spectrometric techniques to quantify ascorbic acid turnover to oxalate.
Description
The purpose of this basic research study is to determine the contribution of endogenous ascorbic acid (AA)turnover to urinary oxalate excretion in both normal BMI and obese adult non-stone formers and calcium oxalate stone formers. The studies proposed will use diets of known nutrient composition, a stable isotope of AA, 13C6-AA, and mass spectrometric techniques to quantify AA turnover to oxalate. Adults (≥19 years) with and without a history of calcium oxalate kidney stone disease will be recruited from within the greater Birmingham area, and divided into normal BMI (BMI\<25 kg/m2) and obes…
Eligibility
- Age range
- 19+ years
- Sex
- All
- Healthy volunteers
- Yes
Inclusion Criteria: * Able to provide informed consent * For stone formers: composition of most recent stone \> 50% calcium oxalate, no uric acid component * For stone formers: first time or recurrent calcium oxalate stone former with stone event within the prior 3 years * Two 24-hour urine collections with urinary 24-hour creatinine excretion within 20% of appropriate ratio of creatinine (mg) / body weigh (kg) for gender * Willingness to stop supplements (vitamins, Calcium (citrate or carbonate) and other minerals, herbal supplements, nutritional aids, probiotics) for 2 weeks before start an…
Interventions
- Dietary SupplementLow Oxalate Diet
Subjects will be instructed to ingest a controlled diet low in oxalate for a total of 4 days
- Dietary SupplementCarbon-13 Ascorbic Acid Oral Load
Subjects will be instructed to ingest 1mg/kg of carbon-13 ascorbic acid at breakfast, 2 days after initiating the low oxalate controlled diet.
Location
- University of Alabama at BirminghamBirmingham, Alabama