Effect of Polyphenols on Absorption of Iron From Sodium Iron Chlorophyllin
Condition: Iron-deficiency
MeSH terms: Iron Deficiencies
Study type: Interventional

Summary: 
      Polyphenols present in tea are known to inhibit the absorption of non heme iron. The
      inhibiting effect of tea on non-heme iron absorption is attributed to the flavonoids present
      in tea. It is well known that Ferrous sulfate is not absorbed well in the presence of
      polyphenols. We would like to evaluate the effect of polyphenols on the newly developed
      compound, sodium iron chlorophyllin (SIC), which mimics the heme iron structure. Comparisons
      of fractional absorption of SIC and Ferrous Sulfate in the presence of polyphenols can help
      identify the performance of the compounds as vehicles for iron delivery in the presence of
      iron absorption inhibitors.

      In a single-blind randomized cross-over study using stable iron isotope technique, iron
      bioavailability from SIC delivered with an inhibitory matrix can therefore be determined when
      given along with black tea
    

Detailed description: 
      New approaches to treat iron deficiency include developing novel iron compounds with possible
      iron absorption routes that increase iron bioavailability and reduce gastrointestinal side
      effects.

      Sodium iron chlorophyllin (SIC) is a water-soluble semisynthetic chlorophyll derivative where
      the magnesium in the porphyrin ring has been substituted by iron. Given the porphyrin ring
      heme-like structure of SIC, it may be an alternative delivery route for iron, suitable also
      for vegetarians and vegans. Yet, there are few studies investigating the use of SIC for this
      purpose.

      We recently completed the study entitled "Evaluation of iron bioavailability from iron
      chlorophyllin in young women using the iron stable isotopic method" based on previous in
      vitro and in vivo studies.. The study showed a 7% fractional iron absorption (FIA) from SIC
      when compared to the control compound, ferrous sulfate, which had a FIA of 30%, indicating a
      Relative Bioavailability of SIC of 20%. The study showed an inverse relationship between
      ferritin status and iron absorption from SIC in the study participants and an increase in the
      FIA in the presence of ascorbic acid. Both these findings lean towards the possibility that
      that the iron contributing to the FIA from SIC may be iron that was dissociated from the
      porphyrin ring of the chlorophyllin and entering the common non heme iron pool. This inverse
      relationship in ferritin and FIA is well known for ferrous sulfate. However, one cannot
      confirm the pathway taken up by SIC to deliver iron based on the previous study alone.

      Polyphenols present in tea are known to inhibit the absorption of non heme iron.The
      inhibiting effect of tea on non-heme iron absorption is attributed to the flavonoids present
      in tea. There are several types of tea flavonoids: monomers (catechin), dimers (theaflavin),
      and polymers (thearubigin). Black tea contains 10% flavanols, 25% catechins, 20% theaflavins
      and 45% thearubigins. The mechanism of iron absorption inhibition by tea is by formation of a
      complex of the flavonoids with iron. It is mainly the galloyl group in these phenolic
      compounds that specifically binds iron. A cup of black tea, brewed with 2.5 g tea leaves
      contains about 200 mg tea flavonoids . Heme iron absorption has also been shown to be
      inhibited by the presence of polyphenols but unclear to what extent. Thus, comparisons of
      fractional absorption of SIC and Ferrous Sulfate in the presence of polyphenols can help
      identify the performance of the compounds as vehicles for iron delivery in the presence of
      iron absorption inhibitors.

      In a single-blind randomized cross-over study using stable iron isotope technique, iron
      bioavailability from SIC delivered with an inhibitory matrix can therefore be determined when
      given along with black tea.

      SIC has been produced at the HNL with a 50% incorporation of iron into the chlorophyll. Our
      protocol is based on a Unilever patent that is no longer active, with in-house adaptation.
      The SIC has a neutral taste and will be presented as a dark green liquid, being the solution
      of SIC in water.

      If SIC, as hypothesized, behaves in a similar way to heme, then iron absorption inhibitors,
      such as the polyphenols, will not have an effect on the absorption of iron from SIC.
    

Intervention name(s): SIC; SIC + tea; FeSO4; FeSO4 + tea
Intervention type(s): Dietary Supplement; Dietary Supplement; Dietary Supplement; Dietary Supplement
Intervention description(s): Sodium Iron Chlorophyllin as prepared by the human nutrition laboratory, ETH Zurich; Sodium Iron Chlorophyllin as prepared by the human nutrition laboratory, ETH Zurich with 2g of tea brewed for 5 minutes; Ferrous sulfate solution serves as a positive control - and whose absorption is well known.; Ferrous sulfate solution given with 2g of tea brewed for 5 minutes - expected iron absorption inhibition
Intervention MeSH terms: Fesoterodine
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: The study will be a randomized, single centre cross over study where every participant will receive all the four interventions.
Masking: None (Open Label)
Primary purpose: Treatment