Doctors have known that a medication often prescribed to treat heart failure is inactivated by gut microbes, particularly a bacterial species called E. lenta. Now scientists have a better understanding of why. A Harvard University research team led by Peter Turnbaugh found that the heart drug digoxin turns on two E. lenta genes that help convert the drug into its inactive form, thereby making the medicine less effective. By measuring gene abundance, the scientists could reliably predict whether a microbial community could break down the drug. The researchers also identified a possible way to stop the process: add protein. Their studies using mice showed that a diet high in protein—and the amino acid, arginine, that helps E. lenta grow—increased digoxin absorption. These initial findings suggest that one day it may be possible to tailor digoxin therapy through diet modifications.
Each year about 1 in 700 babies is born with Down syndrome, a condition that occurs when cells contain three copies of chromosome 21. A new technique offers a proof of principle for silencing the extra copy. Using induced pluripotent stem cells derived from a person with Down syndrome, a research team led by Jeanne Lawrence of the University of Massachusetts Medical School inserted a gene called XIST into the extra chromosome 21. The gene, which normally turns off one whole X chromosome in females, rendered the chromosome copy and most of its genes inactive. The researchers plan to test the approach in a mouse model of Down syndrome and use it to further explore the biology of chromosome errors. The findings could eventually aid the development of therapies to mitigate resulting medical problems.
This work also was funded by NIH’s National Cancer Institute and Eunice Kennedy Shriver National Institute of Child Health and Human Development.
University of Massachusetts Medical School News Release
Aspirin is used often to prevent heart attacks and stroke. Yet, doctors know little about why it’s more effective in some people than others. A team of Duke University researchers, including Geoffrey Ginsburg and Deepak Voora, recently discovered a method to pinpoint the patients who benefit most from the drug as well as those who are at risk for heart attacks. By administering aspirin to a set of healthy volunteers and people with heart disease and then analyzing their gene activity patterns, the researchers identified a set of genes that correlate with insufficient platelet response to aspirin. The finding might lead to a simple blood test to help tailor treatments for heart disease.
NIH’s National Heart, Lung, and Blood Institute also supported this work.
Duke Medicine News Release Ginsburg Bio Voora Bio