Indigestible Disaccharides Open Tight Junctions and Enhance Net Calcium, Magnesium, and Zinc Absorption in Isolated Rat Small and Large Intestinal Epithelium

Abstract

The effects of three indigestible disaccharides on net calcium (Ca), magnesium (Mg), and zinc (Zn) transport in isolated rat jejunal, ileal, cecal, and colonic epithelium were determined. Permeability of fluorescein isothiocynate-dextran-4 (FD4) and transepithelial electrical resistance (TEER), which vary according to tight junction (TJ) activity in the intestinal mucosa, were also determined. The addition of 1-100 mM melibiose, difructose anhydride (DFA) III, or DFA IV to the mucosal medium increased the net absorption of the three minerals and FD4 permeability, while decreasing TEER dose dependently in the four intestinal portions. Positive linear relations were found between the net transport of the three minerals and FD4 passage in all portions of the intestine, whereas negative linear relations were observed between net absorption of the three minerals and TEER. We concluded that the three indigestible saccharides directly affect the epithelial tissue and open TJs, thereby promoting Ca, Mg, and Zn absorption in the small and large intestine in vitro.

Difructose Anhydride III Enhances Zinc Absorption in vivo: Zinc Gluconate is More Suitable for the Effects of Difructose Anhydride III than Zinc Yeast

“…On the other hand, zinc gluconate exists almost entirely as zinc ions in the body. Stimulation of zinc absorption by DFAIII has been demonstrated by in vitro experiments [8], but zinc sulfate, which was used in that study, is not approved as a food ingredient or food additive. The two sources of zinc used in this study, zinc gluconate and zinc yeast, are approved as foods in Japan.…”

“…We thought that the difference in zinc absorption between zinc gluconate and zinc yeast with coadministration of DFAIII was due to differences in their ionization characteristics. It has been reported that DFAIII directly affects epithelial tissue by opening the tight junctions located on the luminal side adjacent to epithelial cells, and that increases in calcium, magnesium and zinc absorption occur by the entrance of these ions through the paracellular route regulated by the tight junctions [12,8]. It is noted that zinc yeast is not very soluble in water, and is difficult to ionize.…”

“…In the small intestine in rats, zinc absorption has been shown to occur in the duodenum, jejunum, and ileum [22]. It has been reported that zinc absorption occurs through the epithelial tissue in the intestine [8]. Zinc absorption is also involved in the zinc transporters, ZnT-1, 2, 3 and 4, which are expressed only in the duodenum and upper jejunum and not in the ileum or colon.…”

“…In recent years, difructose anhydride III (DFAIII) has been suggested to have a positive effect on calcium, magnesium and zinc absorption in vitro [8]. As its safety has been demonstrated by acute and sub-acute toxicity test, DFAIII is a candidate as a food supplement to improve calcium insufficiency.…”

Chemical and Enzymatic Approaches to Carbohydrate-Derived Spiroketals: Di-D-Fructose Dianhydrides (DFAs)

“…For instance, Hara and Tomita have demonstrated that ingestion of α-D-fructofuranose-β-Dfructofuranose 1,2':2,3'-dianhydride (1, also known as DFA III) in daily diet increases the absorption of calcium, magnesium and zinc in rats [38][39][40][41][42][43]. The same authors observed that ingestion of DFA III and DFA IV [di-β-D-fructofuranose-2,6':6,2'-dianhydride (15), a non-spiroacetalic DFA isomer, Figure 4] [44] affects the epithelial tissue and activates the passage of tight junctions in vitro, thereby promoting mineral absorption in the small and large intestine of rats [45][46].…”