The diet of pregnant women increases the risk of asthma in children

According to researchers from Jewish Medical Center and Duke Medical Center, the diet of pregnant mother mice can cause epigenetic changes that increase the risk of allergic asthma in pups. . Pregnant maternal mice have a diet rich in methyl-containing additives, such as folic acid, and pups will have more respiratory allergies than mice with maternal mice that eat food with low methyl content.

The results of the study are published online in the September 18, 2008 issue of Clinical Investigation and will be published in the October edition.

David Schwarts, the author of a paper and professor of medicine at the Jewish National Health Center, said: 'Our findings show that maternal diets alter DNA AND methylation, thereby affecting the development of the fetal immune system, making the fetus more susceptible to respiratory disease. The number of asthma cases that have increased sharply in the last two decades is probably also related to the change in the supplementary diet of pregnant women '.

The prevalence of asthma has nearly doubled in the last 25 years. Asthma currently affects 11% of the US population, and consumes $ 9.4 billion in treatment costs. Although both genes and the environment are linked to the risk of asthma, scientists still cannot find the exact cause of the disease or explain the rate of disease increase.

Epigenetics studies gene regulation rules. The exposure environment may lead to changes in the methyl group (CH3) bound to certain DNA molecules, thereby altering the expression of a particular gene. There are many environmental factors (including diet, cigarette smoke and pharmaceuticals) that can alter the methyl group that binds to DNA, especially during the sensitive period. Ongoing research has shown that epigenetic mechanisms can affect the development of the immune system, both can increase or decrease the risk of developing genetic diseases.

The team decided to test the potential role of epigenetics on the risk of allergic asthma. They fed pregnant mice eating foods with high or low methyl content. In addition to folic acid, the methyl-rich diet also contains high levels of L-methionine, choline and genistein.

New research shows that a pregnant mother's diet can cause epigenetic changes that increase her risk of allergic asthma.(Photo: iStockphoto / Petro Feketa)

When the researchers examined pups based on the model of allergic asthma, they found that maternal mice who ate a lot of methyl were more likely to have asthma, a higher respiratory response, and more susceptible. Respiratory response is higher, and there is a higher rate of IgE in the blood. They also found that T cells seem to be linked to allergies. Male mice also make their descendants more susceptible to respiratory allergies. In contrast, mice with a methyl-rich diet during lactation or maturity did not increase susceptibility to the disease.

Co-author John W. Hollingsworth, an assistant professor of medicine at Duke University School of Medicine, said: 'During the development of the uterus, there is an extremely important stage when the pups are very sensitive. with epigenetic changes that change its immune system. Epigenetic changes may partly explain why we have had so many difficulties in identifying genes associated with the risk of asthma, the genetic change effect may have been epigenetic changes. cover up or suffer from it making it more complicated '.

When the researchers analyzed the mouse's genome, they found 82 genes that were significantly more methylated in mice with a high methyl diet. The 10 highest methylation genes are biological causes of asthma. They are transcription factors that control the expression of many genes, as well as genes involved in cell migration and respiratory allergies. High methylation genes also exhibited lower levels of low methylation genes in mice that were fed a low-methyl diet.

This study shows that too much folic acid (and other complementary foods) during pregnancy can increase the risk of asthma and allergies, and even play a role for it. statues have increased asthma in the last two decades. The US public health service recommended in 1992 that all pregnant women should eat 400 micrograms of folic acid daily to reduce the risk of congenital brain and spinal defects in children . In 1996, the US Food and Drug Administration required folic acid to be added to flour, bread and certain grains to prevent birth defects. Studies have demonstrated these measures help reduce birth defects in children.

Talking about the important role of folic acid supplementation to prevent birth defects, Dr. Schwartz and Hollingsworth have not made any changes in the supplementary dosage, indicating that this problem needs to be studied. Save more deeply.

Refer:
1. Hollingsworth et al. Airway disease in mice with utero supplementation with methyl donors enhances. Journal of Clinical Investigation, 2008; DOI: 10.1172 / JCI34378
2. Rachel L. Miller.Prenatal maternal diet of asthma risk in offspring.Journal of Clinical Investigation, 2008;DOI: 10.1172 / JCI37171