Simultaneous supplementation with iron and folic acid can affect Slc11a2 and Slc46a1 transcription and metabolite concentrations in rats
BRITISH JOURNAL OF NUTRITION
Authors: Radziejewska, A.; Suliburska, J.; Kolodziejski, P.; Chmurzynska, A.
Abstract
The present study aimed at analysing how dietary folic acid (FA) and Fe deficiency, followed by supplementation with these nutrients, affects the expression of folate and Fe transporters in the duodenum, as well as FA and Fe status. After a deficiency period, Wistar rats were randomised to a group fed with a diet deficient in FA and supplemented with Fe (DFE), a diet deficient in Fe and supplemented with FA, a diet supplemented with Fe and FA (FEFOL), a diet deficient in Fe and FA (D) or a control diet (C). Tissue collection was performed after 2, 10 or 21 d of these diets. Group D had higher Slc11a2 mRNA levels than the DFE group at every time point and there were differences in mRNA levels of Slc46a1 between the DFE and the FEFOL groups at the third time point, but we observed no differences in protein levels between the groups. The DFE and D groups not only had lower serum folate concentrations at every time point but also had the highest homocysteine concentrations. Total Fe binding capacity concentrations were the lowest in the DFE group at the first time point and in the DFE and the FEFOL groups at the final time point. Simultaneous supplementation with FA and Fe resulted in significantly higher Hb concentrations than did supplementation with these nutrients alone. Our findings indicate that dietary FA and Fe deficiency, and subsequent supplementation with these nutrients, affects transcription but not the protein levels of FA and Fe transporters in the duodenum.
Three-dimensional structure of transmembrane domain 6 of natural resistance associated macrophage protein 2 in hexafluoroisopropanol aqueous solution
SPECTROSCOPY LETTERS
Authors: Xiao, Shuyan; Dong, Zhongping
Abstract
Natural resistance associated macrophage protein 2 plays an important role in adsorption of a broad range of divalent metal ions, including iron, cobalt, zinc, copper, nickel, manganese, cadmium and lead. The protein contains 12 putative transmembrane domains, two highly conserved and mutation sensitive histidines were found in the predicted transmembrane domain 6, mutation of two histidines at either or both sites causing deficiency of function. In this paper, the structure of the peptide from transmembrane 6 of natural resistance associated macrophage protein 2 was investigated in 60% hexafluoroisopropanol aqueous solution by circular dichroism and nuclear magnetic resonance spectroscopy. Our study demonstrated the peptide forms a discontinuous alpha helix structure with two helices spanning over Ala256-Ile259 and Asn268-Ser278.