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Effect of folate–binding protein on intestinal transport of folic acid and 5–methyltetrahydrofolate across Caco–2 cells

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Summary

Background

Milk products are a potential matrix for fortification with synthetic folic acid or natural 5-methyltetrahydrofolate (5–CH3–H4folate) to enhance the daily folate intake. In milk, folate occurs bound to folatebinding proteins (FBP). Our previous studies with an in vitro gastrointestinal model showed that 70% of the initial FBP content of the milk product was retained in the duodenal lumen. While folic acid remained bound to FBP after gastric passage, 5–CH3–H4folate was mainly present as free folate in the duodenal lumen.

Aim of the study

To investigate the effect of FBP on the absorption of folic acid and 5–CH3–H4folate from the intestinal lumen.

Methods

The transport of [3H]–folic acid and [14C]–5–CH3–H4folate across enterocytes was studied in the presence or absence of bovine FBP using monolayers of Caco–2 cells grown on semi–permeable inserts in a two–compartment model. The apparent permeability coefficients (Papp) of folic acid and 5–CH3–H4folate were determined and compared with the permeability of reference compounds for low (mannitol) and high (caffeine) permeability.

Results

The transport from the apical to the basolateral side of the Caco–2 cells was higher (P < 0.05) for folic acid (Papp = 1.7*10–6 cm/s) than for 5– CH3–H4folate (Papp = 1.4*10–6 cm/s) after 2 h incubation to 1 µM folic acid or 5–CH3–H4folate test solutions (pH 7). The permeability of folic acid and 5–CH3–H4folate across Caco–2 monolayers appeared to be higher (P < 0.05) than that of mannitol (Papp = 0.5*10–6 cm/s) but lower (P < 0.05) than that of caffeine (Papp = 34*10–6 cm/s). The addition of FBP to the medium led to a lower (P < 0.05) intestinal transport and cellular accumulation of folic acid and 5–CH3–H4folate.

Conclusions

Compared to the reference compounds, folic acid and 5–CH3–H4folate showed a moderate permeability across Caco–2 cells, which indicates that folate absorption from the intestinal lumen is not likely to be complete. The intestinal transport of folic acid and 5–CH3–H4folate was found to be dependent on the extent of binding to FBP at the luminal side of the cells.

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References

  1. Fishman SM, Christian P, West KP (2000) The role of vitamins in the prevention and control of anaemia. Public Health Nutr 3:125–150

    CAS  PubMed  Google Scholar 

  2. Wald N, Sneddon J, Frost C, Stone R (1991) MRC Vitamin Study Group Prevention of neural tube defects. Results of the Medical Research Council Vitamin Study. Lancet 338:131–137

    Article  PubMed  Google Scholar 

  3. Daly LE, Kirke PN, Molloy A, Weir DG, Scott JM (1995) Folate levels and neural tube defects. J Am Med Assoc 247:1698–1702

    Article  Google Scholar 

  4. Rampersaud GC, Bailey LB, Kauwell GPA (2002) Relationship of folate to colorectal and cervical cancer: review and recommendations for practitioners. J Am Diet Assoc 102:1273–1282

    Article  PubMed  Google Scholar 

  5. Boushey CJ, Beresford AA, Omen GS, Motulsky AG (1996) A quantitative assessment of plasma homocysteine as a risk factor for vascular disease. J Am Med Assoc 274:1049–1057

    Google Scholar 

  6. Graham IA, O’Allaghan P (2000) The role of folic acid in the prevention of cardiovascular disease. Curr Opin Lipidol 11:577–587

    Article  CAS  PubMed  Google Scholar 

  7. De Bree A, Van Dusseldorp M, Brouwer IA, Van het Hof KH, Steegers-Theunissen RP (1997) Folate intake in Europe: recommended, actual and desired intake. Eur J Clin Nutr 51:643–660

    Article  CAS  PubMed  Google Scholar 

  8. Konings EJM, Roomans H, Dorant E, Goldbohm R, Saris W, van den Brandt P (2001) Folate intake of the Dutch population based newly established liquid chromatography data for foods. Am J Clin Nutr 73:765–776

    CAS  PubMed  Google Scholar 

  9. Swiatlo N, O’Conner DL, Andrews J, Picciano MF (1990) Relative folate bioavailability from diets containing human, bovine and goat milk. J Nutr 120:172–177

    CAS  PubMed  Google Scholar 

  10. Ghitis J (1967) The folate binding in milk. Am J Clin Nutr 20:1–4

    CAS  PubMed  Google Scholar 

  11. Wagner C (1985) Folate Binding Proteins. Nutr Rev 43:293–299

    CAS  PubMed  Google Scholar 

  12. Salter DN, Scott KJ, Slade H, Andrews P (1981) The preparation and properties of folate-binding protein from cow’s milk. Biochem J 193:469–476

    CAS  PubMed  Google Scholar 

  13. Holm J,Hansen SI (2001) Binding of radiolabeled folate and 5-methyltetrahydrofolate to cow’s milk folate binding protein at pH 7.4 and 5.0. Relationship to concentration and polymerization equilibrium of the purified protein. Biosci Rep 21:733–743

    Article  CAS  PubMed  Google Scholar 

  14. Verwei M, Arkbåge K, Havenaar R, van den Berg H, Witthöft C, Schaafsma G (2003) Folic acid and 5-Methyltetrahydrofolate in fortified milk are bioaccessible as determined in a dynamic in vitro gastrointestinal model. J Nutr 133:2377–2383

    CAS  PubMed  Google Scholar 

  15. Arkbåge K, Verwei M, Havenaar R, Witthöft C (2003) Addition of folate-binding protein lowers the bioaccessibility of folic acid and 5-methyltetrahydrofolate from fortified yogurt as studied in a dynamic in vitro gastrointestinal model. J Nutr 133:3678–3683

    PubMed  Google Scholar 

  16. Verwei M, Arkbåge K, Mocking H, Havenaar R, Groten J (2004) The FBP binding characteristics during gastric passage are different for folic acid and 5-CH3H4 folate as studied in a dynamic in vitro gastrointestinal model. J Nutr 134:31–37

    CAS  PubMed  Google Scholar 

  17. Said HM, Grishan FK, Murrell JE (1985) Ontogenesis of the intestinal transport of 5-methyltetrahydrofolate in the rat. Am J Physiol 249:567–571

    Google Scholar 

  18. Said HM, Strum WB (1983) A pH-dependent, carrier-mediated system for transport of 5-methyltetrahydrofolate in rat jejunum. J Pharmacol Exp Ther 226:95–99

    CAS  PubMed  Google Scholar 

  19. Selhub J, Powell GM, Rosenberg IH (1984) Intestinal transport of 5-methyltetrahydrofolate. Am J Physiol 246:G515–G520

    CAS  PubMed  Google Scholar 

  20. Said HM, Grishan FK, Redha R (1987) Folate transport by human intestinal brush-border membrane vesicles. Am J Physiol 252:229–236

    Google Scholar 

  21. Colman N, Hettiarachchy N, Herbert V (1981) Detection of a milk factor that facilitates folate uptake by intestinal cells. Science 211:1427–1429

    CAS  PubMed  Google Scholar 

  22. Salter D, Blakeborough P (1988) Influence of goat’s-milk folate-binding protein on transport of 5-methyltetrahydrofolate in neonatal-goat small intestinal brush-border-membrane vesicles. Br J Nutr 59:497–507

    Article  CAS  PubMed  Google Scholar 

  23. Said HM, Horne DW, Wagner C (1986) Effect of human folate binding protein on folate intestinal transport. Archiv Biochem Biophys 251:114–120

    CAS  Google Scholar 

  24. Tani M, Fushiki T, Iwai K (1983) Influence of folate binding protein from bovine milk on the absorption of folate in gastrointestinal tract of rat. Biochim Biophys Acta 757:274–281

    CAS  PubMed  Google Scholar 

  25. Hidalgo IJ, Raub TJ, Borchardt RT (1989) Characterization of the human colon carcinoma cell line (Caco-2) as a model system for intestinal epithelial permeability. Gastroenterology 96:736–749

    CAS  PubMed  Google Scholar 

  26. Hillgren KM, Kato A, Borchardt RT (1995) In vitro systems for studying intestinal drug absorption. Med Res Rev 15:82–109

    Google Scholar 

  27. Vincent ML,Russell RM, Sasak V (1985) Folic acid uptake characteristics of a human colon carcinoma cell line Caco- 2. A newly described cellular model for small intestinal epithelium.Human Nutrition: Clinical Nutrition 39C:355–360

    Google Scholar 

  28. Artusson P, Karlsson J (1991) Correlation between oral drug absorption in humans and apparent drug permeability coefficients in human intestinal epithelial (Caco-2) cells. Biochem Biophys Res Com 175:880–885

    PubMed  Google Scholar 

  29. Yazdanian M, Glynn SL, Wright JL, Hawi A (1998) Correlating partitioning and Caco-2 cell permeability of structurally diverse small molecular weight compounds. Pharm Res 15:1490–1494

    Article  CAS  PubMed  Google Scholar 

  30. Yee S (1997) In vitro permeability across Caco-2 cells (colonic) can predict in vivo (small intestinal) absorption in man – fact or myth. Pharm Res 14:763–766

    Article  CAS  PubMed  Google Scholar 

  31. Grès M-C, Julian B, Bourrié M, Meunier V, Roques C, Berger M, Boulenc X, Berger Y, Fabre G (1998) Correlation between oral drug absorption in humans, and apparent drug permeability in TC- 7 cells, a human epithelial intestinal cell line: comparison with the parental Caco-2 cell line. Pharm Res 15:726–733

    Article  PubMed  Google Scholar 

  32. Rubas W, Jezyk N, Grass GM (1993) Comparison of the permeability characteristics of human colonic epithelial (Caco-2) cell line to colon of rabbit, monkey, and dog intestine and human drug absorption. Pharm Res 10:113–118

    Article  CAS  PubMed  Google Scholar 

  33. Van den Berg H, Finglas PM, Bates C (1994) FLAIR intercomparison on serum and red cell folate. Int J Vitam Nutr Res 64:288–293

    CAS  PubMed  Google Scholar 

  34. Faassen F, Kelder J, Lenders J, Onderwater R, Vromans H (2003) Physicochemical properties and transport of steroids across Caco-2 cells. Pharm Res 20:177–186

    Article  CAS  PubMed  Google Scholar 

  35. Duizer E, Penninks AH, Stenhuis WH, Groten JP (1997) Comparison of permeability characteristics of the human colonic Caco-2 and rat small intestinal IEC-18 cell lines. J Contr Rel 49:39–49

    Article  CAS  Google Scholar 

  36. Forssén KM, Jägerstad MI, Wigertz K, Witthöft CM (2000) Folates and dairy products: a critical update. J Am Coll Nutr 19:100S–110S

    PubMed  Google Scholar 

  37. Shane B (1995) In: Bailey LB (ed) Folate in Health and Disease, Marcel Dekker, Inc., New York, pp 1–22

  38. Cichowicz DJ, Shane B (1987) Mammalian folylpoly-γ-glutamate synthetase. 2. substrate specificity and kinetic properties. Biochem 26:513–521

    Article  CAS  Google Scholar 

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Author notes

  1. H. van den Berg

    Present address: The Netherlands Nutrition Centre, Den Haag, The Netherlands

Authors and Affiliations

  1. Physiological Sciences Dept., TNO Nutrition and Food Research, 360, 3700 AJ, Zeist, The Netherlands

    M. Verwei, H. van den Berg, R. Havenaar & J. P. Groten

Authors
  1. M. Verwei
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  2. H. van den Berg
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  3. R. Havenaar
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  4. J. P. Groten
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Correspondence to M. Verwei.

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Verwei, M., van den Berg, H., Havenaar, R. et al. Effect of folate–binding protein on intestinal transport of folic acid and 5–methyltetrahydrofolate across Caco–2 cells. Eur J Nutr 44, 242–249 (2005). https://doi.org/10.1007/s00394-004-0516-9

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  • DOI: https://doi.org/10.1007/s00394-004-0516-9

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