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Updated: May 20, 2026
11:56
A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells
Published on: April 11, 2014
Association between the plasma proteome and serum ascorbic acid concentrations in humans
Laura A Da Costa1, Bibiana García-Bailo, Christoph H Borchers
1Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, ON, Canada M5S 3E2.
The Journal of Nutritional Biochemistry
|July 31, 2012
Summary
This study identified several plasma proteins, including complement C9 and vitamin D binding protein, inversely associated with vitamin C (ascorbic acid) levels. These findings suggest vitamin C may regulate novel physiological pathways.
Area of Science:
- Nutritional Biochemistry
- Proteomics
- Human Physiology
Background:
- Vitamin C (ascorbic acid) is linked to reduced chronic disease risk, but its biological pathways are not fully understood.
- Identifying proteins regulated by vitamin C can elucidate its physiological roles.
Purpose of the Study:
- To identify plasma proteins associated with circulating ascorbic acid levels using a proteomics approach.
- To explore potential novel physiological functions of vitamin C.
Main Methods:
- A proteomics approach was employed on plasma samples from 1022 healthy young adults.
- Mass-spectrometry-based multiple reaction monitoring measured 54 abundant plasma proteins.
- Statistical analyses (ANCOVA) compared protein concentrations across serum ascorbic acid tertiles, adjusting for covariates.
Main Results:
- Seven plasma proteins, including complement C9, ceruloplasmin, alpha-1-anti-trypsin, angiotensinogen, complement C3, vitamin D binding protein, and plasminogen, showed inverse associations with ascorbic acid levels.
- The inverse association between ascorbic acid and vitamin D binding protein was more pronounced in individuals with higher serum 25-hydroxyvitamin D levels.
Conclusions:
- Circulating ascorbic acid levels are significantly associated with several plasma proteins involved in diverse physiological pathways.
- These associations suggest potential novel physiological effects and regulatory roles of vitamin C beyond current understanding.
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