Ignite Creation Date:
2024-05-05 @ 11:33 AM
Last Modification Date:
2024-10-26 @ 9:09 AM
Study NCT ID:
NCT00071526
Status:
RECRUITING
Last Update Posted:
2024-07-15
First Post:
2003-10-27
Brief Title:
Urinary Vitamin C Loss in Diabetic Subjects
Sponsor:
National Institute of Diabetes and Digestive and Kidney Diseases NIDDK
Organization:
National Institutes of Health Clinical Center CC
Study Overview
Official Title:
Urinary Vitamin C Loss in Subjects With and Without Diabetes
Status:
RECRUITING
Status Verified Date:
2024-08-29
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
None
Brief Summary:
Several studies have reported that diabetic subjects have lower plasma vitamin C concentrations than non-diabetic subjects Although urinary vitamin C loss in diabetic subjects was reported to be increased in two studies these are difficult to interpret due to lack of controlled vitamin C intake inadequate sampling lack of control subjects or methodology uncertainties in vitamin C assay and sample processing Consequently it is unclear whether diabetic subjects truly have both low plasma and high urine vitamin C concentrations We propose that low plasma vitamin C concentrations in diabetic subjects are due in part to inappropriate renal loss of vitamin C in these subjects but not in healthy controls We will study nondiabetic controls and cohorts with diabetes Vitamin C concentrations in plasma RBCs and urine will be measured in outpatients In those willing to be admitted to the Clinical Center we will measure vitamin C pharmacokinetics to determine the relative bioavailability for vitamin C in individuals with and without abnormal urinary loss of vitamin C or renal leak Single nucleotide polymorphisms SNPs will be determined in genomic DNA responsible for the two proteins mediating sodium dependent vitamin C transport SVCT1 and SVCT2 We will also explore mechanisms underlying abnormal urinary vitamin C loss
Detailed Description:
Several studies have reported that diabetic subjects have lower plasma vitamin C concentrations than non-diabetic subjects Although urinary vitamin C loss in diabetic subjects was reported to be increased in two studies these are difficult to interpret due to lack of controlled vitamin C intake inadequate sampling lack of control subjects or methodology uncertainties in vitamin C assay and sample processing Consequently it is unclear whether diabetic subjects truly have both low plasma and high urine vitamin C concentrations We propose that low plasma vitamin C concentrations in diabetic subjects are due in part to inappropriate renal loss of vitamin C in these subjects but not in healthy controls We will study nondiabetic controls and cohorts with diabetes Vitamin C concentrations in plasma RBCs and urine will be measured in outpatients In those willing to be admitted to the Clinical Center we will measure vitamin C pharmacokinetics to determine the relative bioavailability for vitamin C in individuals with and without abnormal urinary loss of vitamin C or renal leak Single nucleotide polymorphisms SNPs will be determined in genomic DNA responsible for the two proteins mediating sodium dependent vitamin C transport SVCT1 and SVCT2 We will also explore mechanisms underlying abnormal urinary vitamin C loss
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
False
Is a FDA Regulated Device?:
False
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None
Secondary IDs
| Secondary ID | Type | Domain | Link |
|---|---|---|---|
| 04-DK-0021 | None | None | None |