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A Rapid and Specific Microplate Assay for the Determination of Intra- and Extracellular Ascorbate in Cultured Cells
Published on: April 11, 2014
Gut transport of a molybdenum/ascorbic acid complex
M S Russell1, J Bailey, S J Duffy
1Department of Biology, Mount Allison University, Sackville, New Brunswick, Canada.
Drugs in R&D
|March 18, 2006
Summary
The transport of a molybdenum/ascorbic acid complex in the small intestine appears to be energy-independent and non-saturable. This suggests the absorption mechanism is not protein-mediated, offering insights into trace element absorption.
Area of Science:
- Gastroenterology
- Trace Element Metabolism
- Pharmacokinetics
Background:
- Limited research exists on mammalian small intestine trace element absorption.
- A molybdenum/ascorbic acid complex shows potential as an oral insulin-mimetic agent.
- The intestinal transport mechanism of this complex remains uncharacterized.
Purpose of the Study:
- To investigate the intestinal transport mechanism of a molybdenum/ascorbic acid complex.
- To utilize elemental molybdenum measurements as an indicator for complex transport.
- To determine if transport is energy-dependent and saturable.
Main Methods:
- Everted rat small intestine sacs were employed for transport studies.
- Incubation with a molybdenum complex, with and without 2,4-dinitrophenol (oxidative phosphorylation inhibitor).
- Concentration-dependent transport was assessed using varying molybdenum complex levels.
Main Results:
- Transport rates were not significantly affected by 2,4-dinitrophenol, indicating energy independence.
- A significant positive linear correlation was observed between complex concentration and transport rate.
- Results suggest a non-saturable transport process.
Conclusions:
- The primary mechanism for molybdenum/ascorbic acid complex transport in the small intestine is energy-independent.
- The non-saturable nature implies the process is not protein-mediated.
- Findings contribute to understanding trace element absorption pathways.
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