Effect of retinol on iron bioavailability from Iranian bread in a Caco-2 cell culture model.
OBJECTIVE
Iron and vitamin A deficiencies are among the most prevalent nutritional problems. There are no data on iron bioavailability in Iran. In addition, interaction of vitamin A with iron bioavailability is not well documented, so we determined iron bioavailability from the most widely consumed food in Iran, lavash bread, and the effect of vitamin A on this bioavailability.


METHODS
In vivo human studies for determining iron bioavailability are cumbersome, time consuming, and costly to perform, so we used an in vitro model in Caco-2 cells. Bread samples were digested with or without vitamin A (10 microg/1.0 g of dried bread). We used an iron solution containing vitamin C as a positive control. Iron absorption was measured using 59FeCl3. Bioavailability was defined as the percentage of radiolabeled iron taken up and transferred by Caco-2 cells after 1.5 h of incubation. Experiments were carried out two to four times.


RESULTS
Mean +/- standard deviations for iron bioavailability in bread samples digested without or with additional vitamin A and in controls were 2.53 +/- 1.55%, 6.62 +/- 3.40%, and 20.80 +/- 2.30%, respectively (P < 0.001). Vitamin A caused a 2.62-fold increase in iron absorption from bread samples.


CONCLUSIONS
Iranian lavash bread has low iron bioavailability, but this can be increased by vitamin A supplementation. Increasing vitamin A intake can be considered as a method for increasing iron bioavailability, thus combating iron and vitamin A deficiencies simultaneously.
Gargari
Bahram Pourghassem
BP
Department of Nutrition and Biochemistry, Nutrition Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. bahrampg@yahoo.com
Razavieh
Seyed Valee
SV
Mahboob
Soltanali
S
Niknafs
Behrooz
B
Kooshavar
Hossein
H
D001682:Biological Availability; D001939:Bread; D018938:Caco-2 Cells; D006801:Humans; D066298:In Vitro Techniques; D007492:Iran; D000090463:Iron Deficiencies; D007504:Iron Radioisotopes; D019266:Iron, Dietary / Q000493:pharmacokinetics*; D014801:Vitamin A / Q000494:pharmacology*; D014802:Vitamin A Deficiency / Q000517:prevention & control; D014815:Vitamins / Q000494:pharmacology*
D007504:Iron Radioisotopes; D019266:Iron, Dietary; D014815:Vitamins; D014801:Vitamin A