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    Sorry NPR Listeners, This Meat, Egg And Dairy Nutrient Is Essential For Brain Development
    By News Staff | November 28th 2013 06:00 AM | 4 comments | Print | E-mail | Track Comments

    Asparagine, which is found in foods such as meat, eggs, and dairy products, was once considered non-essential because it is also produced naturally by the body.

    And that is true, for every organ except the brain, where the amino acid is essential for normal brain development. 

    "The cells of the body can do without it because they use asparagine provided through diet. Asparagine, however, is not well transported to the brain via the blood-brain barrier," said senior co-author of the study Dr. Jacques Michaud, who found that brain cells depend on the local synthesis of asparagine to function properly. 

    In April 2009, a Quebec family experienced the worst tragedy for parents: before the age of one, one of their sons died of a rare genetic disease causing congenital microcephaly, intellectual disability, cerebral atrophy, and refractory seizures. The event was even more tragic because it was the third infant to die in this family from the same disease. This tragedy led Dr. Michaud to discover the genetic abnormality responsible for this developmental disorder.

    The team identified the gene affected by the mutation code for asparagine synthetase, the enzyme responsible for synthesizing the amino acid asparagine. The study is the first to associate a specific genetic variant with a deficiency of this enzyme. "In healthy subjects, it seems that the level of asparagine synthetase in the brain is sufficient to supply neurons," Michaud said. "In individuals with the disability, the enzyme is not produced in sufficient quantity, and the resulting asparagine depletion affects the proliferation and survival of cells during brain development."


    Potential treatment

    Children who are carriers of this mutation suffer, to varying degrees, from a variety of symptoms, including intellectual disability and cerebral atrophy, which can lead to death. The Quebec family lost three infant sons to this disorder. Two of their other children are alive and healthy.



    A genetic defect disrupts brain development by affecting the synthesis of asparagine, an amino acid until now thought to be non-essential. The discovery was made by researchers at CHU Sainte-Justine and the University of Montreal. This image shows MRI Images taken from a child who later died from the defect. Credit: Universite de Montreal. 

    Knowledge about gene mutations can be used to develop treatments. "Our results not only open the door to a better understanding of the disease," Michaud said, "but they also give us valuable information about the molecular mechanisms involved in brain development, which is important for the development of new treatments."

    For example, asparagine supplement could be given to infants to ensure an adequate level of asparagine in the brain and the latter's normal development. "The amount of supplementation remains to be determined, as well as its effectiveness," said the geneticist. "Since these children are already born with neurological abnormalities, it is uncertain whether this supplementation would correct the neurological deficits."

    To date, nine children from four different families have been identified as carriers of the mutation: three infants from Quebec, three from a Bengali family living in Toronto, and three Israelis, whose symptoms are less severe.

    Dr. Michaud's team discovered the genetic mutation by comparing the complete DNA of the Quebec family's children with symptoms of the disease. The researchers then identified children, among other families, who carried the single candidate gene. The gene was revealed only in the affected children, but not in the unaffected children of the families studied.

     "We are not at the verge of a miracle drug," says Michaud, "but we at least know where to look."  


    Comments

    Thanks for alerting us of one more nutrient essential for the brain found in animal products. The others? B12, carnosine, DHA (ALA in vegetables does not convert well into DHA), and creatine. If you are a vegetarian you need to supplement of (gasp!) eat some meat.

    @Deane and "News Staff" (you need to put your name on things like this):

    Although asparagine is an essential amino acid in the way you mention, this is a very rare genetic mutation, as you yourself point out in the article. As we do need it for healthy brain development, we should really get it, but it turns out this is found in lots of foods, not just meat, dairy, and eggs. It is simply found in higher concentrations there. If people who don't eat these foods need more, they simply take a supplement, like healthy vegans and elite athletes everywhere. Speaking as a vegan marathoner and a compassionate human, there was no need to turn this family's pain into a political statement on diet. As my wife just commented, this is enough to get supporters like us to stop supporting NPR. Please watch it in the future.

    Okay, am I the only one who's going to ask this? NPR is mentioned in the headline, but nowhere in the article. As an NPR listener, I was seduced into reading a story that had nothing to do with NPR. If there's a link, perhaps you should identify it in the article.

    NPR has actually been on a nonstop pro-meat tear ever since the Kroc (McDonald's) widow left them a fortune. Asparagine is widely available in plant foods such as nuts and seeds, whole grains, soy, legumes, and of course, asparagus, but as stated in the article, "Since these children are already born with neurological abnormalities, it is uncertain whether this supplementation would correct the neurological deficits." What was the point of this article?