Vitamin A concentrations in liver determined by isotope dilution assay with tetradeuterated vitamin A and by biopsy in generally healthy adult humans

Abstract

The vitamin A status in 11 generally healthy surgical patients was estimated by measuring the dilution of a 45-mg oral dose of tetradeuterated retinyl acetate (99% pure). After purification of retinol by high-performance liquid chromatography, the ratio of 2H4-retinol:1H-retinol in plasma was measured by gas chromatography-mass spectrometry. On the basis of the observed ratios of [2H4]retinol:[1H]retinol over 19-47 d, the total body reserves and liver concentrations of vitamin A were calculated. Liver biopsy samples taken at surgery were directly analyzed for vitamin A. The correlation coefficient between calculated and measured liver vitamin A concentrations for 10 of the subjects was 0.88, and the Spearman's rank correlation coefficient was 0.95 (p less than 0.002). Thus, total body reserves of vitamin A in humans can be estimated validly in the marginal and satisfactory ranges by a benign, relatively noninvasive procedure.

Determination of vitamin A content from selected Nigerian fruits using spectrophotometric method

“…The carrot can trace its ancestry back to thousands of years originally having been cultivated in central Asia and Middle East. Recently there has been renewed interest in examining bio-availability factors of vitamin A by using more quantitative stable isotope techniques for measuring whole-body stores in response to controlled intakes spread around the world following some Spanish research work (Adams and Green, 1994;Furr, 1989;Haskell, 1998;Maron, 2014). Also by following post absorption carotenoids in the triacylglycerol-rich lipoprotein fraction ( Van and Van, 1998;Castenmiller and West, 1998).…”

Feasibility of using retinol-binding protein from capillary blood specimens to estimate serum retinol concentrations and the prevalence of vitamin A deficiency in low-resource settings

“…There should be careful interpretation of these estimates as a reflection of the total VA pools in the body 20 . At the same time, there are no viable alternative indicators of VA stores, so the use of RBP as a surrogate indicator to estimate low serum retinol concentrations has important practical relevance for programmes.…”

Evaluation of the “Olson Equation”, an Isotope Dilution Method for Estimating Vitamin A Stores

“…In 1989, Furr and colleagues in Olson's lab presented an isotope dilution equation (see below) for assessing vitamin A status in humans [2]. Since then, this "Olson equation" or "deuterated retinol dilution (DRD) equation" has been fruitfully used to estimate stores or to evaluate interventions in a number of human studies (for example, see references [3 -5]).…”