Researchers at the Albert Einstein College of Medicine of Yeshiva University have found the mechanism by which the B vitamin folatea crucially important nutrientis absorbed by the intestinal tract. Their findings, published in the December 1 issue of the journal Cell, solve a longstanding mystery as to how folates in the diet are absorbed and pave the way for a genetic test that can save the lives of infants who lack the ability to absorb folate.
We cant live without folate, says Dr. I. David Goldman, the studys senior author and director of the Albert Einstein Cancer Center. Adequate folate in our diet --and our small intestines ability to absorb it -- are crucial for synthesizing DNA and other important constituents of our bodies. Folate deficiency in the developing embryo can cause developmental nervous-system defects such as spina bifida. After birth, infants with folate deficiency can experience anemia, immune deficiency with severe infections, and neurological defects such as seizures and mental retardation. And in adults, folate deficiency has been associated with an increased risk of certain cancers.
A water-soluble vitamin such as folate cant readily penetrate the fatty membrane of cells. It needs a specialized uptake mechanism so it can be absorbed by intestinal cells and ultimately enter the bloodstream. The Einstein researchers identified the membrane protein, dubbed PCFT/HCP1, that transports folate molecules from the small intestines acidic milieu into intestinal cells. A study published last year aroused considerable scientific fanfare when it reported that this protein ferried heme linked to iron (which becomes hemoglobin when coupled with the protein globin) into intestinal cells. But the Einstein study shows that folate transport is the primary function of this protein.
The Einstein study also showed that a mutation in the PCFT/HCP1 gene is responsible for hereditary folate malabsorption, a rare but potentially fa
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Contact: Karen Gardner
kgardner@aecom.yu.edu
718-430-3101
Albert Einstein College of Medicine
30-Nov-2006