Congenital heart defects are the most common form of human birth defect, but we still don't fully understand what causes them. Previous research had suggested that some heart defects could be triggered by problems with the placenta, the organ that provides oxygen and nutrients to the developing embryo. Now, researchers at Nanjing University, China have confirmed this link by focusing on a protein whose levels are reduced in many patients with congenital heart defects , called SLC25A1.
SLC25A1 plays a key role in transporting citric acid, an important metabolite whose derivatives can affect gene expression , to different regions of our cells. However, it was unclear how the protein's loss might be linked to congenital heart defects. By disrupting this protein in different tissues in developing mice, the researchers have shown that loss of SLC25A1 does not affect the developing heart directly.
Instead, it leads to problems with placental growth and this, in turn, causes heart defects in the mice. Their study was published in the journal Development on 26 November 2024. The researchers used gene-editing tools to produce mouse embryos that completely lack the SLC25A1 protein.
As expected, these embryos developed heart defects. However, they also had problems with their placentas, which were thinner than usual. "A rapidly increasing number of studies in mice have suggested that the placenta is involved in the regulation of embryonic heart development ," explained Professor Zhongzh.