KYOTO -- A research team has discovered a new compound that inhibits a gene which is one of the causes of intellectual disability in people with Down syndrome, the team announced on Sept. 4.
Made up of members including professor Masatoshi Hagiwara of Kyoto University's Graduate School of Medicine, the team verified that administration of the compound in pregnant mice carrying fetuses with Down syndrome led to improvements in the fetuses' condition -- in terms of brain structure abnormalities and learning capability.
With the number of pregnant mothers who check chromosomal abnormalities such as Down syndrome before birth increasing, it is thought these latest study findings might enable treatment of human fetuses during the fetal stage.
Down syndrome is the most common chromosomal abnormality, and occurs in approximately 1 in every 1,000 people. The condition occurs when a person has an extra copy of chromosome 21, making growth of nerve cells difficult, which in turn leads to conditions such as intellectual disabilities in many cases.
The research team screened a total of 717 candidate compounds as it searched for one that could trigger the growth of nerve cell-creating neural stem cells. The one that yielded promising results in preclinical studies has been labeled, "Algernon."
The team orally administered Algernon to the pregnant mice once daily, and found that the fetuses' brain cortex did not become thinner, which is a typical characteristic of Down syndrome. In addition, after the mice with Down syndrome were born, they performed in a similar way to mice without the condition in a maze study, which tested learning capability.
According to the team, Algernon is thought to have rectified brain structure abnormalities as well as improved learning ability in the mice by inhibiting the action of a particular gene, thus enabling the normal growth of neural stem cells. It has also been confirmed that neural stem cells created from the induced pluripotent stem (iPS) cells of people with Down syndrome grow normally when the compound is administered.
The team of scientists plans to conduct research on the use of the compound for other nerve-cell related conditions such as infarction, Alzheimer's disease, and Parkinson's disease.
Speaking on the research, Hagiwara says, "There are lots of tough challenges relating to safety. It is also necessary for antenatal treatment to be accepted by society."
A paper on the team's discovery is set to be released in the American publication, "Proceedings of the National Academy of Sciences" in the near future.