What is the mechanism of Sodium Ferrous Citrate?

Sodium ferrous citrate is a compound often used in the treatment of iron deficiency anemia, a common condition where the body lacks enough healthy red blood cells due to insufficient iron. Understanding its mechanism requires delving into how this compound operates within the body to address iron deficiencies.

Sodium ferrous citrate is a coordination compound where iron, in its ferrous (Fe^2+) state, is chelated by citric acid. This chelation stabilizes the iron in a soluble form, aiding its absorption in the gastrointestinal tract. The body preferentially absorbs iron in its ferrous form, as it is more soluble and bioavailable than ferric (Fe^3+) iron. Once ingested, sodium ferrous citrate dissociates in the acidic environment of the stomach, releasing ferrous ions and citrate.

The released ferrous ions then enter the duodenum and upper jejunum, where they are absorbed by enterocytes, the cells lining the gut. This absorption is facilitated by divalent metal transporter 1 (DMT1), a protein that specifically transports divalent metal ions across the cell membrane. Once inside the enterocytes, ferrous iron can either be stored as ferritin or transported into the bloodstream.

To enter the bloodstream, ferrous iron must be converted to its ferric form. This oxidation process is catalyzed by hephaestin, a ferroxidase enzyme located on the basolateral membrane of enterocytes. The ferric iron is then bound to transferrin, a plasma protein that transports iron through the blood to various tissues, including the bone marrow where it is used in the synthesis of hemoglobin, or to the liver for storage.

Citrate, the other component of sodium ferrous citrate, plays a dual role. First, it acts as a chelator, making iron more soluble and thus more readily absorbed. Second, it acts as an antioxidant, helping to maintain the integrity of the ferrous iron and preventing its premature oxidation to the less absorbable ferric state before it reaches the absorptive sites in the gut.

Therefore, the mechanism of sodium ferrous citrate can be summarized as a series of processes, whereby the compound provides a stable, bioavailable form of iron that is efficiently absorbed in the gastrointestinal tract, transported via the bloodstream, and utilized by the body to correct iron deficiency anemia. This ensures that the vital functions of iron, such as oxygen transport, DNA synthesis, and electron transport, are effectively maintained.

Overall, sodium ferrous citrate offers an effective means of addressing iron deficiencies due to its stability, solubility, and bioavailability, making it a valuable therapeutic agent in the treatment of iron deficiency anemia.